Go for the 10D if you can afford it, its by far the best of the 3.
The 300D is basically a 10D in a plastic case (as opposed to magnesium alloy
) and with a few less manual controls.
The D60 you will only be able to get second hand now since the 10D has effectively replaced it.
In terms of lenses, if you can afford them go for L series lenses since they will offer the best quality throughout the zoom and aperture range. Im only a student so I cant afford premium lenses like that, but I do have the 75-300 f4-5.6 USM IS
which I find is very good for what it is, but the sharpness tends to drop off at the higher end of the zoom scale.
Also when you buy, don't forget your accessories
- you will definitely need a spare battery, my 10D takes about 300 shots and the battery dies after that.
- since the camera is 6.3mp (all of them) the images recorded are very high in size, and in raw format they can be 6-8mb so consider a large size compact flash card (512mb +). Don't bother with Microdrives they are too slow since they are essentially miniature hard drives and take time to spin up and access sectors etc. Also because its a physical moving device it will eat more battery than a solid state compact flash card for example.
Hope this helps