I bought something similar to this:http://cgi.ebay.com/ws/eBayISAPI.dll...135332231&rd=1
Mine is older and uses the pcmcia slot, though.
They also make them using firewire ports.
I haven't really looked around, but ebay is the best place I've found to get them. Plus, they're really cheap. After you transfer your stuff, you can use your old hd as an external.
I can't tell you how many people's a**es I've saved using this thing. Every time someone's computer would crash at my school and they were told they had to reinstall everything and lose all their stuff, I just took their harddrive, they got their papers etc, and everyone was happy. The only downside is you'll have to wait a week or so to get it. Maybe you can get it express.