mosrite.
heres something to try on your ibm laptop.
powertracks that i use works on any laptop ive tried it on.
the sound quality purely depends on the interface you use as everything is 32 bit float and 64 bit in the critical areas. ie very high quality tracks.
its a breeze to install. if your laptops up to it youll get 48 tracks potentially max.
if you doubt me try the demo from pgmusic.com.
you can then export your tracks into pro tools if you wish as wave files.
the reason i suggest you look into it also is it has a fail safe built in....ie a recovery feature just in case a pc has a problem.
as to the interface to your thinkpad you might want to contact pg tech support at the site who have always helped me. i seem to remember a topic awhile back on interfaceing to your type of interface.(pcmcia). with an external sound device.
an option might be for the gig if you dont have a firewire interface rent a
enabled laptop for the gig. and hook up a RME for example maybe ??
just an idea.
addendum....
a couple of powertracks users i believe are useing this pcmcia sound interface amd like the sound. apparently claims mastering grade convertors.
http://www.zzounds.com/item--EMU1616M