Save yourself the trouble and do not buy a Canon LBP6000 laser printer! It will not run under Ubuntu 12.04 LTS "Precise Panglion" (32-/64-bit).
Just a quick notice on a printer I recently bought totally confident with my previous excellent Ubuntu printer support experience. Previous laser printers I had like two of the Brother HL line (HL-2030 and HL-2070N) worked out-of-the-box. Not so with the LBP6000.
I spent several hours trying every trick I found on the web. There is quite a number of users struggling with this printer. My conclusion after a weekend of try and constant error is that the LBP6000 does not print under Ubuntu 12.04. I tried both 32- and 64-bit Ubuntus. Basically I’m presented with the problem presented here. It apparently installs flawlessly, however refuses to print a page.
It seems though, as if the printer was working on previous Ubuntu versions, but not on todays most recent LTS version (october 2012).