at that price range you'll find sweet Canons and Nikons. Either way you go, you'll get a great camera. I say check out the Nikon D3100 and D5000 and the comparable Canons. Then...go to a camera store to actually hold them and use the menus and buttons. does it "feel" right? do the controls make sense to you? Does it fit well in your hands?
As much fun as I have with the Canon vs. Nikon game - they are the tops and you really can't go wrong with either.
You may want to research those fancy new mirrorless interchangeable lens cameras? (pricey, but cool). the SOny NEX3/5 and the Lumix GF1(?) are pretty cool. they are smaller than a DSLR, have interchangable lenses and give excellent image quality.
I hope that helps get you started.