Since this seems to be a hot topic right, now here's a list of places to get art of your D&D/TTRPG characters without using other artists' work/OCs without permission!

Feel free to add to this, it's definitely not exhaustive

Heroforge: https://www.heroforge.com/ 
Customise a 3D image of your character and, if you like it, pay for it to be 3D printed as an actual mini. They have colour options now too

Reroll: https://reroll.co/ 
An app that lets you make your character in pixel art

Official art!
If you're using a module, official art of some NPCs should be provided.

Token/character art packs
Some artists sell packs of ready-made art available for use in your games. You can find a lot on the Roll20 marketplace! https://marketplace.roll20.net/ 

Character creators/Picrew

There are loads of great avatar makers out there, which are really customisable! Just make sure you read the creator's terms, which will often specify how you can use the image and how to credit.

And of course:

Commission artists!!
The best way to get art of your character made specifically for you, and to support artists, is to commission them. Some artists (like myself ) can also design a character from scratch if you don't know what they look like yet

Don't have money but really like an artist's work?

Ask the artist!
Some artists might be happy for you to use their existing art in a home game, but it's only polite to check first. DON'T just assume it's fine!

As someone who's had my OCs used for RP, and had people telling me they're using them in their games, it's an uncomfortable experience. For many artists, their characters are extremely personal - an extension of themselves, or sometimes a way to work through personal issues

Way too often I see people asking for advice on where to get art for tokens, NPCs etc only to see replies such as "just take art you see on the internet." Why, when there are so many other options out there to allow you to make characters that are really yours?

My block button has had some real good exercise lately so just as a heads-up, if anyone plans to come at me with some "you should be grateful your art was used" nonsense, you're going straight in the bin

That aside I hope this thread was helpful and feel free to add suggestions!

As an extra note, the invitation to share resources was intended for character creation tools, not for people to promote their own commissions on my page - especially when they don't even follow me. Please don't do that. There are dedicated art share threads to show off your work

Thank you so much to everyone who's been adding suggestions to this thread! I muted it uhhh a while back because I don't like too many notifs, but it's appreciated! Anyone checking out these resources, be sure to check out the comments too