I wouldn't recommend the Chinese Ebay copies though
All the best Brett
google search and/or ebay search
I have searched ebay for batteries in the past. I found the copies and I also found the oem batteries available. I checked the sellers and the people selling the copies had good feedback, as good as the people selling oem's. At the time 3 people in my immediate family had Dell computers and 2 of the 3 of us had battery problems so I figured that if the oem batteries were that bad the copies couldn't be any worse. I picked the seller that sounded the best and had the best feedback, bought a battery, and had no problems with it. YMMV.
I would recommend you buy through Amazon... as if faulty , they have a good returns policy...