This plaques me.  Everytime I need to scan something, my scanner still isn't working.  (Like it's going to fix itself).  So, it's time to fix it.  And, I'm going to document the process to help you along the way.  

 Okay, to get started, here are some links that I've tracked down.  Linux is going to need a windows based driver to make the Visioneer work right. 

Visioneer Scanner drivers for Linux
http://www.littlecms.com/iphoto/otlinux.htm
http://viceo.orcon.net.nz/

 My current system:

Ubuntu Feisty Fawn

Here are the SANE packages that I have installed (you're gonna need these):

snovak:/etc/sane.d$ dpkg -l | grep sane
ii  libsane                                    1.0.18-3ubuntu1                            API library for scanners
ii  sane-utils                                 1.0.18-3ubuntu1                            API library for scanners -- utilities
ii  xsane                                      0.99+0.991-1ubuntu2                        GTK+-based X11 frontend for SANE (Scanner Ac
ii  xsane-common                               0.99+0.991-1ubuntu2                        GTK+-based X11 frontend for SANE (Scanner Ac
 

I am also going to try VueScan (doesn't work)

A kernel patch: http://www.kernel.org/pub/linux/kernel/people/gregkh/usb/2.4/usb-scanner-3-2.4.21-pre3.patch
Looks like we're going to patch the kernel.  (sigh)  http://ubuntuforums.org/showthread.php?t=84174 doc on patching the kernel.

snovak:/usr/bin$ sane-find-scanner
 found USB scanner (vendor=0x04a7 [Visioneer], product=0x0321 [OneTouch 8100 EPP/USB]) at libusb:002:004

snovak:/usr/bin$ scanimage -L
No scanners were identified.

  Well I know what chipset I need to get working now:  E5.. super http://www.qbik.ch/usb/devices/showdev.php?id=1072

  Hmm.. gave up for today. Maybe i'll try again later.