I have a question about this part of Rule #4 regarding my signature. The image is from Photobucket, and I don't remember who uploaded it. Is my Donators violating this rule in any way?In general, posting or having in your signature anybody else's artwork or text without appropriate credit is considered a fairly severe inadvertent offense, though exceptions will be made if the artist can sensibly be considered obvious (such as in the case of official video game art, screenshots and the like) or if the creator explicitly allows the work to be used without attribution.
Also, where can I find the rules for signatures in general?
Thanks for the help!