You just need mining software that's supported by ubuntu. Then type in the pool's address into the mining software. I'm sure most mining software is compatible. Here's one that looks pre-built and should work: http://ck.kolivas.org/apps/cgminer/cgminer-3.1.1-x86_64-built.tar.bz2
I just downloaded and extracted the file, but I am not sure how to install the software using Ubuntu 12.10? There is no Install or .exe