To get this working, here are the steps to take:
1) You need some usb libraries, so, in a terminal type:
sudo apt-get install libusb-dev build-essential libsane-dev
2) To get the sane backends from git you need git-core. If you don't already have it, type this (also in a terminal):
sudo apt-get install git-core
3) Now use the git that was just installed to get the sane backends using the following command:
git clone git://git.debian.org/sane/sane-backends.git
That downloads the backends and puts them in a folder called sane-backends in your home folder.
4) Change directory into the new sane-backends folder and compile them:
cd sane-backends
./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
make <--- this one takes a while
sudo make install
Now everything is installed, but you still won't be able to scan (except as root) until you set up some permissions.
5) You need to edit a file, but you need to be root to edit it, so:
sudo gedit /lib/udev/rules.d/40-libsane.rules
and add the following 2 lines:
# Canon CanoScan Lide 100
ATTRS{idVendor}=="04a9", ATTRS{idProduct}=="1904", ENV{libsane_matched}="yes"
save the file, exit gedit, exit terminal, reboot, and...
SCAN AWAY!
Instructions modified version of Shutter4U's post.
