Personally, throwing my two cents into the keyboard / mouse arena...
If you're typing a lot, or want exact precision, buy a mechanical keyboard. They're expensive, but completely worth it - the amount of fatigue you lose and typing speed you gain... It's worth it. I thought it was pointless till I tried one - now I'm a convert. (If you aren't, I LOVE the comfort curve 2000 - it's not heavily ergonomic, and EXTREMELY well built - my mother has one that's never been cleaned, had drinks spilled on it many times, is five years old, and still types perfectly.)
As for a mouse, I personally don't like many 'gaming' mice - they feel uncomfortable. (Even the legendary g9x hurt.) I'd go with one of two things: A simple, well built 5-button mouse (I like the Intellimouse Explorer 3.0 and the Comfort 6000 - as a bonus, Microsoft has good macro software.) or: an extremely nice mouse that's either customizable or that you can try out somewhere to feel the fit.
The only things to avoid are these two brands: Razor (Yeah, they have some nice stuff, but it's EXPENSIVE, and built to only last 6 months - that ads up quickly) and MadCatz, which is a crapo rip-off brand.
^I like the deathadder shape, but I've found it to be of extremely bad build quality - I had two of them die on me within months before I stopped going with them. The two mice I mentioned have the same shape and number of buttons, and, personally, feel better.