I had good luck with Lacie drives.
http://www.lacie.com/products/range.htm?id=10007
Also buying a case and then putting your own drive in it is a good way to go. I have this one and I'm happy with it.
http://eshop.macsales.com/Catalog_It...em=OWCMEFWU2A6
These cases are nice and they support both USB2 and FireWire, just add your own ATA drive.
Western Digital Hard Drives I think are the best.
http://www.wdc.com/en/
I buy everything mail order
http://www.warehouse.com/
Or any of the other ones, there are a bunch of them. You should see how many catalogs are in my mailbox each week.