I dno why people are telling you to pick up nikons 50/1.8 as it got no AF-motor built-in, which you'd need for d3000.
I also have a nikon d3000, and my first buy after the kit lens was a macro lens, tamron 90/2.8, awesome one!
BUT, you should know what you want before buying, if you want to catch the detail in everyday-subjects/other stuff you
should get a macro lens, if you like to catch landscapes and that kind of stuff, a wide angle is the shit for you. A zoom is nothing I ever used so I can't help you out there.
Anyway, good LUCK with your photographing, d3000 is a nice beginner camera
