Folks interested in open data sources to augment their own local data resources might find this source of some interest.
This catalog is created and maintained through the efforts of OpenGeoCode.Org and Crowdsourcing.
http://opengeocode.org/opendata/index.php
This can be daunting. However it can lead to a large variety of data.
Good Luck. If you find things that are particularly useful. Please share with others here.