Not sure if it's been asked in here, but anyways I've got a D40 right now and have the kit lens and a 55-200mm lens. I'm really interested in picking up a fisheye lens for it as well. What would you guys recommend, and on average how much do they tend to cost? I'm not looking to spend an outrageous amount at the moment. Any help is really appreciated.
The Nikon 10.5mm fisheye is $590 at B&H and Adorama, and that's the cheapest fisheye Nikon makes. Tokina makes a 10mm fisheye for Nikon dSLR's and that's around $550. I'd personally go with the Tokina; it's cheaper and similar quality. Either lens would need to be manually focused with a D40, so that factor doesn't need to be worried about.