Government tax foreclosures and bank foreclosures are two different roads which lead to the previous owner losing their property.
The Dept. of Treasury has a web site which will inform you on not only tax foreclosed properties, but also the sale of personal property which this department took: http://www.treas.gov/index.html
VA repos http://www.ocwen.com
These are the direct sites for VA and HUD repos.
I am a VA approved listing broker and have done many HUD and bank repos. Fell free to contact me if you have any other related questions.