Affordable but good fisheye lens (SLR)?

The situation is that id like to get a fisheye/wide angle lens for my Nikon D60 for pictures of skateboarding and maybe other stuff.
i know in photography and lenses its "you get what you pay for" but I'm on a tight budget, i guess the most i'd be able to spend is about 350, so can someone point me in the direction of a decent starting fisheye/wide angle lens for an affordable (for me) price.cheers.

I have this lens, and I can strongly recommend it. It doesn't have autofocus or automatic aperture, but neither of these affect its use, really. The depth of field with a fisheye lens is almost infinite, so just set the focus almost to infinity and you'll never need to touch it again. Likewise, set the aperture to f/5.6 and put your camera in aperture-priority mode and let the camera handle the exposure by altering the shutter speed.

The optical quality is good overall, and excellent for the price. All this comes in at under $300. Have a look at the review (second link below). The Rokinon lens is exactly the same as the Samyang and Vivitar 8mm lenses. The Opteka 6.5mm is very, very similar.

Http://www.photojojo.com/store/awesomeness/fisheye-lens
^ $50-85 and completely reliable.