What different sigma 70-200mm?

What different sigma 70-200 are there and what is the difference
I'm winging a new 70-200mm 2.8 for my nikon D90 and can't spend £1600 for a Nikon one so I like the sigma's
But what one I don't now!
Can any one please tell me what difrent ones are there out there?
On eBay there's so meny and the prices go from £110 - £2000 what can worent that much difrents and do I need it?

Have you visited the Sigma website.

On that site, they list all their lenses and not which ones are auto-focus.

Since you have a D90, ANY auto-focus lens will work with your camera

I avoid buying anything that is not new from sites like eBay. There's no way to assure that the lens or camera is not just damaged junk, someone is trying to dump

Www.adorama.com and www.keh.com are the two used photographic equipment dealers that are both trustworthy, and able to ship internationally, including UK. They know what they are doing and rate their used equipment accurately. I've used them both for slightly used equipment and have never been disappointed. Prices are very reasonable.

Adorama currently has a slightly used first generation Nikon 70-200 G for around £1020.It's rated -EX, meaning the glass is completely clean and the outside of the lens shows just minor wear and dings.

http://www.adorama.com/...24449.html

You might be able to wing that price. It outperforms the Sigma Version.

Sigma has a website http://www.sigmaphoto.com/...photo.com/