Please don't consider this your best option, because I'm new to driverpacks and don't know anything about sysprep... But it sounds to me that using the DPINST.exe and DPInst.xml as explained at http://forum.driverpacks.net/viewtopic. … 806#p17806 might do what you are looking for. There is more info at http://forum.driverpacks.net/viewtopic. … 805#p17805 and a more automated way of doing it using Warm Snow's method at http://forum.driverpacks.net/viewtopic.php?pid=17805 .
I'm only offering this info for you to look into until the experts reply. They are pretty busy.
Oops! Wait, I think I might have misunderstood you. I gave info about using the driverpacks. I'm not sure if you are talking about using driverpacks or just assembling the drivers for your PC. If that is what you mean then http://unattended.msfn.org/unattended.xp/view/web/33/ might help. Especially the Drivers From CD section found at http://unattended.msfn.org/unattended.xp/view/web/35/ .
I hope that helps.
Ed