Noob question

A 30D is an older mid range camera while a 1000D is a newer entry level.

The current models are effectively the 60D and the 1100D. Obviously the 60D is better than the 1100D but this may not apply with the older models. The 30D has a metal body, the 1000D is plastic. The 1000D will have a better sensor (low light performance, more pixels) while the 30D will have potentially better ergonomics for bigger hands. The screen on the back of the 1000D is much better than the 30D.

Also these are most likely secondhand so shutter count is important, like car mileage. The 30D will have a more robust shutter while the newer 1000D will probably have a lower count.

I'd go with the newer camera, the 1000D.