I might not be the only one to tell you this, but have you handled all three yet?They are all pretty similar in terms of function and price. What I did before I got into any particular brand was piss off the people in Jessops trying out both Canon and Nikon (several models in each) to work out which felt the easiest to use, easiest to hold etc.Went for Nikon (D100 to start with), as the Canon felt a bit cheap. I have since tried a Sony and it was good (don't know which model though).Mind you - what Dave says about the D60 is true - it means that most of the second hand lenses on the market won't work with it. Perhaps a second-hand D80 (£300) might suit?Good luck with your search.
if you consider a 2ndhand 30D then get a 20D instead and save yourself £50ish. it's a better camera.
A bit of an off-topic Nikon question... When using a DX format camera with a DX lens, do you get the focal lengths the lens claims or do you still have to take into account the 1.5x increase in focal length due to the crop sensor?So for example on the 18-70 DX kit lens, do you actually get an 18mm focal length or a 27mm f.length?