As it turns out, this is a pretty straight forward thing to do.

First we stop the the print spooler. I like doing this from the command line like so:

but you can just as easily stop the spooler from the "Services" control panel applet.

The next step is to delete the temporary files that store the data that is to be sent to the printer:

Finally we restart the print spooler, again from the CLI:

Credit where credit is due, this info I pulled from http://www.ghacks.net/2008/12/11/how-to-deal-with-stuck-print-jobs/ There were a lot of results when I search Google, but this one went straight to the point (I like that).