I was surfing NotebookReview.com, another forum I frequent, and I came across a post that mentioned that there are many external hard drives at Office Depot that are available for rock bottom prices:
|605975||WD My Book||500GB||$32.93|
|613890||WD My Book World Edition||500GB||$44.93|
You cannot buy these online – website shows normal prices. You must buy them instore. Also note that this is the third time these hard drives are marked down so many of them might already be sold out – YMMV. You can try calling in advance and have the store hold the item for you but unfortunatly there are many dishonest workers out there. Once they hear about the rock bottom prices they might just tell you they are out of stock and then go in the back and reserve a handful for themselves. So my suggestion would be to print out the above list, go to your local store and see if they have them. When in store, tell them the item number – you probably will not find the items on display. Good luck! I am going to pick at least one or two of these if possible.
Here is a PDF file for anyone that wants to print this list: CheapHDs.PDF 
Update: Bloody hell there is no Office Depot in my city. What kinda messed up place is this.