I haven't had a bad experience with amibay yet. The mods I've come in contact with have been very helpful no matter how stupid my questions have been.
The other thing that amibay is great for is getting in contact with other hardware guru's and getting some great kit. i.e. 8MB module from Tom and internal IDE from Mika.
Didn't know these guys existed until discovering amibay.
EAB is another great forum, plenty of good threads/forums about hardware mods and photos to look at.
Amiga.org has been my home base for awhile, through red/blue splits/being sold etc.