Bought (and sold) quite a lot of photo equipment at
eBay, and my experience was good.
However, I strongly recommend you to take good care of what you do: try to get to know the seller, try to get some kind of guarantee for the product (particularly with digital cameras, I would say), avoid ultra-bargains, etc. Once you get used to
eBay, I would say it is not difficult to identify scam attempts -which is obviously the most worrying risk you'll face.
If you work a little on all this, you will likely end up saving quite a lot of money, and very happy with what you get. That was my case more than once, I can tell you!

But do take care with your purchases, and don't rush to the first nice offer you find.
You'll find tips and experiences at eBay using the search tool here at the forum. That's been discussed a few times, and some of the more experienced users' comments will surely help you.
Good luck!