What kind of lens would fit my Nikon D3000?

I'm looking into buying some new lens for my Nikon D3000 I just need to know what type of lens will fit my camera

There are two different Nikon 3000 camera bodies. Here's what Nikon says: http://support.nikonusa.com/...-d40x,-and

If you want a lens that is fast and works good in low light then consider the Nikon 35mm f/1.8G. Its a great and inexpensive lens. Here's a review to help you in making a decision:
http://www.amazon.com/...17SWB9VFU/
You can get it from here for a discounted price:

I think most DSLR nikon camera lenses work on most Nikon DSLRs. Thats what I've been told.

You need to look for lenses that have AF-S written in their name.
Like, 50mm f/1.8D will not work, while 50mm f/1.8G AF-S will focus! The first one will fit on your camera, but won't auto focus.
Here's a Lens Buying Guide - http://www.the-dslr-photographer.com/2009/11/buying-a-lens/

Sounds like it's time for you to read the instructions that came with your camera to find out.

With Nikon D3000 any Nikon AF-S lens will work