In my attempts to reach 100% completion in Sonic Advance 3, I found the guides available online for finding the hidden Chao in each level frustrating. All I could find are all text guides, raw gameplay that just expects you to copy what the player does, and maps of the levels that require pixel hunting to find the Chao and are even missing a few of them. I decided to edit these maps to highlight where all of the Chao can be found in a way that can't be easily missed. I also think it's a lot more fun to find your way around a level yourself using a map than it is to just copy exactly what a video does. It also gives you a much broader view of the level layout than gameplay does. I started making these map edits for myself, but hopefully, if anyone else comes across this page, they'll find them useful too.
If you want to check out the original maps without my edits, you can find them at soniccentral.org.
Sonic Advance 3's hubworlds (which the game confusingly calls "Maps") are much smaller and only contain one Chao each, so I don't think it's necessary to make edits of those, but I've included links to them below for convenience. These hubworld maps (or "Map maps" lol) were made by BanjoSonic and can be found at sonicgalaxy.net.