I would suggest getting the personal learning edition of Aliasstudio 2008. It’s newer than V13 and can be downloaded free from the Autodesk site.
As far as what laptop, the software will RUN on just about anything thats out, but if you want an ideal experience I would suggest:
Intel Core Duo CPU (standard on most machines nowadays, avoid the AMD or single core processors)
2 gigs of ram
A dedicated video card, no onboard graphics. At least 128 megs of ram, preferably Nvidia (I generally have seen Nvidia chips handle CAD software better than ATI boards)
At least a 15" screen with as high a resolution as possible.