Just a quick suggestion for all those running into problems with scanner (or printer) drivers for later versions of windows, or if you've moved from windows to an intel Mac.
If you have a reasonably well spec'ed machine, you can run an older operating system (that your scanner drivers support) in a virtual machine. You just need to get hold of something like VMWare Server (free), VirtualBox (free/open source) or if you're on a Mac, Parallels (commercial) or VirtualBox. You then run both the main and virtual machines at the same time.
Install the VM software, create a virtual machine with minimal specs, then install your old operating system. Install all the utilities and drivers you need as if it were a "normal" machine. You will need to ensure that your virtual machine can "see" the USB or SCSI ports (this is configurable, not always a default). Then setup a shared drive on the host computer so you can transfer files back and forth.
If you are on Linux, you can also run VMWare Server or VirtualBox. If you have a recent (VT enabled) chipset, you can run a Xen enabled kernel.
Hope this helps someone.