Importing From Bugzilla
We offer a script for importing bugs from Bugzilla into FogBugz. This file is called importBugzilla.asp on Windows systems and importBugzilla.php on Unix and Mac systems. To get started, bring it up in your browser like this:
Windows: http://YOUR-FOGBUGZ-SERVER/importBugzilla.asp
Unix: http://YOUR-FOGBUGZ-SERVER/importBugzilla.php
Mac: http://YOUR-FOGBUGZ-SERVER/importBugzilla.php
All Other Tools
For those of you looking to import from something other than Bugzilla: The wide variety of database formats in use for the wide variety of bug trackers in existence makes it hard to devise an import feature that could handle all of them. So, to import your data, you would need to use a database tool. The FogBugz database is pretty straightforward with mostly self-explanatory names, so figuring out a one-to-one mapping of the fields from your existing database to ours should not be too hard. We do offer a 90 day no questions asked money back guarantee, so you could try it and if it just isn't working out we will refund your purchase.
If you're using SQL Server, DTS (Data Transformation Services) provides a very intuitive interface for doing this. MS Access has import tools as well. If you're using MySQL, click here for a list of conversion utilities.