How to know what Nikon to get?

My friend has nikon d3000 and this other chick has nikon d5000 and i don't know wtf those numbers mean, and i'm confused as to which one i should get… And thats its not TOO expensive: s

The numbers for Nikons refer to the scale on the quality; the D5000 is not as good as the D3000, and going down in product numbers you eventually end up with their best products being the lowest numbers. If you are looking to buy your first DSLR, then you should definitely looks at your two friends cameras that you stated as being great options to start out with.

Hope that helps!

John Smith is mistaken, the D3000 is a lower entry level model, while the D5000 is the upper entry level model.

Nikon's current in production lineup is as follows, from low to high end:

D3000
D3100 and D5000 (i tend to rate them as about equals)
D90
D7000 and D300s (approximately equals, depending on the field)
D700
D3s and D3x (each the very best in its respective field)