I'll move this to the Player Creation area of the forums as its asking about art supplied by the community.
If you are looking for others to make you some pixel art, you can check out these areas of the forum:
Player Creations, Art, & Literature
This section holds a lot of various art created by the forum members
Terraria Drawings, Paintings, & Pixel Art
Specifically this section of the forums will have Terraria Pixel Art. You can browse around to see if any pixel artists are taking requests. Be sure to read over things thoroughly to make sure you're requesting properly, some artists have different requirements.
Art Request Megathread
Be sure to read over the instructions completely before making a request.