Which fisheye lens is best for my camera?

Recently Purchased a Sony NEX FS-100 camera for use with my filming but I'm a little inexperienced with the riff-raff and technicalities of all of the lens qualities and such that comes with it all. Basically, I've got a 77mm AF-S Nikkor 24-120mm 1.4G Lens that I'm going to attach onto the Sony with an adapter. I'm simply looking for a fisheye lens to slot onto that but I can't seem to find one anywhere without it saying 'make sure it fits with this', and do you have the 'so-and-so' to go with it or 'you can't have "this" without "this"!', it all seems a bit of a struggle for such a simple request!

Price isn't much of an issue, though I've seen fisheye's reach as high as £1400 which is just ridiculous. Obviously, cheapest is best for me - I've seen them go for as low as £20 for the quality I'm looking for (but that goes back to the first paragraph. Apparently this particular one wouldn't fit my lens.) - as long as it has the 'fisheye' look, that's all I care about for now. Qualities and preferences will come later when I'm a little more experienced!

Neow

I take it you are looking for one of the screw on fisheye lenses, and don't care about quality. You can sort through these to match your budget and requirements.
http://www.amazon.co.uk/...n.co.uk/s/

Rokinon makes an E-mount 8mm F2.8 Fisheye lens for Sony NEX cameras and Walimex makes an E-mount 8mm f/3.5 Fisheye does as well.

Look on amazon.co.uk for more details on those lenses