FishBase.org is a great resource for accurate information about the wild conditions of any fish. It is used and maintained by scientists so it is NOT just another hobbyist site regurgitating hobbyist misinformation. It is a great source for the actual maximum size, temperature, distribution, water chemistry, diet, etc. for any type of fish.
YourFishStuff.com is a great place to buy unique foods such as Golden Pearls. They also sell a great line of their own pellet foods.