I've just brought a Canon 400D body on E-Bay for £220, and after some research ended up paying the same again for a refurbished 29-135mm IS Canon lens. If when you think you have settled on a lens, read the reviews at:
Nikon / Nikkor (APS-C) Lens Tests
Filter wise, yes a good UV filter will protect the front lens element from dirt and scratches, don't buy a cheap one as they cause reflection problems, a lens hood is a good thing as it also helps reduce reflections, a rubber one is fine as you can peel it back out of the way at wide angles to prevent vignetting. The only other filter I have bothered with is an infra-red one but that's just for experimentation really.
As for RAW, it's the best for quality, but do all your adjustments of the image in that format and then make a copy of it as a jpg etc keeping the original RAW so that you can re-work it at any time.