Check out these forums as well for more goldfish specific information in respect to health, care, & feeding- they all have 'stickies' with plentiful information:
Aquapuppies
The Goldfish Keepers
The GAB (goldfish & aquarium board)
If your interested in purchasing quality goldfish (and live in the US), these sites are worth checking as well:
The Goldfish Connection
Raingarden Goldfish
GoldfishNet