(for sake of others searching) --
a. Get a laptop USB cage (laptop to USB)
b. You can get a laptop PATA to desktop PATA adapter (44 pin laptop side, 40 pin data + 4 pin power desktop side) adapter for ~$10. Using this adapter you can plug the drive right into the IDE bus on a PC, or use an external harddrive cage.
c. Use the PATA adapter with a PATA 3.5" cage
If your laptop drive is SATA, adjust directions accordingly -- which I am not entirely sure what that means yet -- I haven't run into hooking a sata laptop drive to a desktop.