There is guidance on their web site (bacula, by the way). Basically, you do traditional mysql dumps (check the mysql web site for options) and back those up with whatever backup software you are using. With bacula you can have run-before scripts that do the mysql dumps. If you want to really manage things for mysql even with multiple databases and servers, including full and incremental (and not have to write your own scripts), you can use ZRM (Zmanda Recovery Manager) for MySQL --
http://www.zmanda.com/backup-mysql.html which is open source, but also has corporate support. You can then take the output from that and back it up with whatever general backup software you choose if you want it on tape.
