Just put in "8200 fan" in an ebay search, you'll find several listings I'm sure.
I have had a coupla 8200's and the fans have died on both of them. I just happen to have a friend in laptop sustaining at Dell. He told me that the 8200/c840 fans have a known design flaw that will result in their bearings going south frequently. Dell never did a hardware revision because the 8200 was not a big seller.
That you got 2 years from yours is good
I went through 2 sets of fans on my first 8200 in w/in the first year. Fortunately Dell replaced them for me both times - was still under warranty. The rub is if you get Dell to replace them, you'll get new fans - but with the same shitty bearing design.