Did you run this as root at a terminal prompt:
sane-find-scanner
You should get some results. Note the location of the scanner (it'll be in the /dev directory). Then as root go to that location in the /dev directory and change the permissions on the device so you can run xsane as user. I like to do this in Midnight Commander (started as root) because I can't remember commands. In MC, the front end to the chown command is Control+x, o. Highlight the /dev you want to change and then do Control=x, c and change ownership as desired. You must do this as root.
After you have made the scanner available to you as user, try
xsane
again. See if xsane now finds your scanner.
--GrannyGeek