Freshwater tanks are relatively easy to keep with a little bit of proper maintenance each week. There are tons of resources on the web if you are a beginner. I'll list some useful sites here:
- 247petshop.com - all the aquarium supplies you will ever need and TONS of decorations to choose from
- Age of Aquariums - great resource page with lots of information and pictures
- fishlore.com - one of my favorite aquarium resources, great tools, great information, almost everything you need to know, including beginner's guides
- aquariumfish.net - also one of my favorite aquarium sites, loads of useful info and you can buy fish you can't find in pet stores - also includes Pet Fish Talk the weekly internet show about fish keeping
Don't forget that aquariums aren't limited to just fish. Snails, frogs, crabs, crawfish, clams, shrimp, and don't forget the aquatic plants!
In my 30 gal. tank right now I have: 3 assorted color platies, 3 harlequin rasboras, 2 tequilla sunrise guppies, 1 tuxedo guppy, 2 albino corydoras catfish, and one black mystery snail
...more about aquarium keeping coming soon!