**Edit** My advice to you on the GPU, would be to pick up a Core 216 Superclocked GTX 260, with rebates you can grab it at newegg for just under $100 (which destroys any other card in that price range)
The reason I suggest this is that there are some really great cards coming out in the near future..and if you have the money to burn getting just ONE of them will be worth your interest.
Good Luck
Its pretty difficult to get a 'strong source' for info when it comes to this stuff, sometimes.
My best suggestions would be to sit on google and read any article you can find on it..while that doesn't guarantee you perfect knowledge, you'll at least be up to par with the rest of us misfits