Adorka Stock - a group of people that make poses. they offer over 1k of poses, use a lot of props, include various body types, make group and solo references, and have a wide range of situations. they also have specific parts of the body for reference, such as hands. the sketch function on their website shows you poses every certain time (you can configure this) and is great for practicing.

JookPub Stock - they make solo poses for art reference. they offer poses in various angles and use various props. they also offer more specific poses, like skirts, hands, and photos with an already established mood.

The Pose Archivists - two people that make poses in various situations and angles, they also use props. they also sell packs , but if you want to check their free stuff i suggest their Deviantart since everything is organized in folders.

jademacalla - he makes stock and reference photos using various weapons and in action scenes, very dinamic poses!

Line of Action - site that hosts various models and includes a practice mode, similar to the sketch function on Adorka Stock. it also has a forum to ask for tips and critiques.

earthsworld - collection of portaits of different people around the world. great for experimenting. some of the pictures also show them doing activities (like horse riding).

Croquis Cafe - (nsfw warning) website with nude models orientated to the study of gesture and anatomy studies, though nothing stops you from using it as pose reference. you have to pay to access most of their content, but you can still find some free stuff on their (I believe now abandoned) youtube channel.

VIShopper - a website that sells and distributes cutouts for architecture and graphic design. while their intended purpose isn’t art, you can make use of their library of people to find specific (very specific) situations. you can filter by gender, age and number of people, as well as some others. the website also includes pictures of some backgrounds and certain natural elements (there’s an entire section for plants).

MrCutout - another website pretty much the same as the previous one. the people catalog is bigger I believe, but you can’t filter by number of people, just couples. it has a section for objects and vehicles, which VIShopper doesn’t.

hikaku sitatter - that one popular website people used to compare their height with the one from their fictional crushes. jokes aside, this tool can be really useful to make a character’s height look appropriate, which can be very difficult sometimes when measuring proportions. it’s also great for comparing heights between characters or people to avoid messing it up when drawing them interacting. it also has a few props to get a better grasp of the heights.

Figurosity - a website for people to make and download poses. the poses are for specific models (they’re like the site’s characters) which are pretty different from each other. it also has some animals. I never used it before, but maybe it’s helpful for someone!

Reference Angle - a website that provides pictures of real life heads of people in the angle you put the 3D model in. you can also pick an expression, accessories, and age range. it’s really nice and it is pretty surprising how many pictures there are.

JustSketchMe - this website is a pose maker. it provides a few free models that you can use to free will. you can change the light source and take screenshots. if you want to save the pose as an editable file, access the pose gallery or unlock more models, you’ll have to pay for the premium version. it also has a downloadable paid version.

DesignDoll - pc software for pose making and model designing. it lets you pose a model in any way you want, including hands. you can change the body proportions with sliders to make from chibis to realistic people, as well as changing the light source and color. you can make certain constructions with it too. if you want to save and download poses, you’ll have to pay for the full version, but the free one has everything else mentioned. it’s the one I use and I really recommend it!

Animals References Masterpost - an extense list of resources. putting this one first since surely has most of what you'll need.

Animal Photo Art References Search - it’s like Reference Angle but with animal heads instead of human ones! you can choose from a range of species and see skull models.

Line of Action - site for practicing different animals, showing you randomly chosen pictures every certain time (you can configure this).

sindos’ Feline Comparison - comparison of different felines with pictures.

pCon.planner - free pc software for designing 3D interiors. you can design spaces and place objects from an online library and lots of stuff. very useful if you want to design a specific interior. the camera lets you take pictures from the angles you want. it’s kinda hard to get a grasp of it, but you can make cool stuff.

The Sims - yes, really. it can be very useful for creating settings and interiors or even natural backgrounds. you can also download free custom content that fans make if you’re looking for something specific that the sims doesn’t have. for this matter, I recommend 4 since it has the best graphics and lots of house customization.

Liam Wong’s art - his work focuses on the urban landscape at night, with great inspiration from sci-fi, neon-noir and cyberpunk. is really nice to get some inspiration and has some interesting angles of the city too.

Paletton - make customized color combinations with an interactive color wheel. something I liked about this website is that you can see the colors you picked in templates to see how they interact with each other.

Coolors - many customization options. you can see the colors as a luminance map, make a palette out of a picture, and pick color combinations based on the color wheel. also available for iOS.

ColorSpace - enter the HEX code for a color an generate around 20 color palettes based on color theory systems.

COLOURLovers - social media-esque where you can share and browse color palettes.

Image to Colors Palette Generator - load a file or enter a URL and get a color palette!

art-res’ color palette generator - click the button and get nine random colors.

320 Color Palette Challenge by DeathInHeavens

Tumblr blogs dedicated to post color palettes - september-color / color-palettesblog / colourpod

In order of my personal most used to least used, these are sites that have free stock pictures and textures: Pexels - Unsplash - Freepik - Pixabay - GraphicBurger

Toptal’s Subtle Patterns - a gallery of patterns you can download for free. useful for clothes, fabric, or just to use as textures or backgrounds.

Free Stock Textures - pretty self explanatory.

COLOURLovers’ Patterns - seamless patterns made by users on the site. you can color a pattern, but you can’t design one since it requires adobe flash and, well.

PNG and texture packs from DeviantArt - a bunch of users upload PNGs in packs you can download. you need an account to get them though. Here are some accounts I’ve downloaded stuff from or just found nice: ungodlybee / GraphicAssets / tvm-resources / ZomToy and many more! it’s very easy to end up downloading everything you see ;; beware of the quality though.

Games Fashion Archive - site that allows you to view 3D models of certain games, including Genshin Impact, Fire Emblem, and others. you can choose to view specific parts of the model (torso, bottom, accessories, etc).

A timeline of women’s fashion from 1784-1970 - drawn examples with a bit of history of the evolution of women's fashion.

an introductory timeline of western women's fashion - examples of clothes with descriptions starting from the 12th century up to 1910. I also suggest checking the op's blog for more info.

Types of suits’ and suits’ parts - drawn examples showing different styles of suits and it's components.

Outfits4Events - site that sells clothes and accessories from various periods of time. intended for costume parties, but can be useful nonetheless.

Lolibrary - gallery of Lolita fashion’s clothes and accessories. you can filter by brands and clothes categories.