Neither, get the d40. It's better for less money. Always spend $$$$$ on lens. They will outlast the camera body anyways. I guarantee it. I'd recommend the d50 even, it has a motor in the body which the d40 lacks so you can autofocus other lenses that the d40 otherwise can't.
The D3000 Nikon's newest inexpensive DSLR. It's a good camera all by itself, but it's the worst DSLR Nikon has ever made. What makes it worse by comparison is significantly slower and balkier operation when compared to other Nikon DSLRs.
The Nikon D40 is a better camera for less money.
The Nikon D3000 is inferior both in operational speed and ease of use, as well as inferior in technical image quality. Specifically, the D3000 is about one stop noisier at any given ISO than the D40; the D3000 is as noisy at ISO 800 as the D40 is at ISO 1,600. While the D40 looks great at ISO 1,600, the D3000 is too grainy at ISO 1,600 for normal use. You have to keep the D3000 at ISO 800 or below for the best results.