Best lenses for nikon D5000 under $300?

Okay thank you!

The 35mm 1.8 prime lens. I leave my prime on my DSLR about 90% of the time and at only 200.00, it is a great deal.

+1 for the 35mm f1.8. Good general purpose lens.

If you're interested in portraits, Nikon have recently launched an AF-S Nikkor 50mm f1.8G which will be more suited for that.

There's also the Sigma 30mm f1.4 DC, it's like the 35mm 1.8, but faster and has a better AF system.

Nikon AF-S DX 35mm f1.8G is indeed a very compact and lightweight lens, measuring only 70x52.5mm and weighing in at just 200 grams. Part of the reason why it is so light is that the outer barrel is made of plastic (and feels so), but at least the lens mount is metal. The Nikon 35mm f1.8G will mount on any Nikon SLR, but - as noted in the Introduction - it is meant to be used on digital SLRs with a DX sized sensor only. Use of this lens on a film body would result in huge amounts of vignetting with completely black corners.