I've never seen a formal list of banned practicioners. Here is what I could gather from the IRS Bulletins (http://www.irs.gov/irb/). If you wish to verify the accuracy of this list, go to google, type "IRS suspension (or disbarred), last name, first name" and google should come up with the IRS Bulletin.
List is updated as of 8/7/2014
https://docs.google.com/spreadsheets/d/ ... sp=sharing
Format Excel 2007. I promise I've not attached any viruses. Should be able to click on the blue box " Click here to start download from sendspace". The file is called Book2.xlsx
https://www.sendspace.com/file/t87kgs
This was just the first free file sharing website I could find. If someone has a better option let me know, thanks. My intent with this was to spread word of the bad preparers. I was originally going to paste all their names here so that google could crawl and if people searched their names they could find them. But figured that would make a huge thread and complicate things.