You have got 2 good answers from these 2 buyers. I have helped a police officer to buy a GNND home last year. They couldn't be more happier. It has to be a HUD house, contact any HUD approved agent in your market to help you with the bidding and check for availability. They are not available often, and you get it by lottery form, your HUD agent will submit the bid for you, and you will know the result after the deadline expires. Once you got the bid, you have 48 hours only to get the contract executed, earnest money, loan pre-approval letter all send out to the HUD office within 48 hours, or you will lose the bid. My advice is make sure you are pre-approved before bidding, cash ready for the earnest money, (it has to be bank cashier's check).
I have wrote a blog on http://www.activerain.com and also posted here on Trulia, please feel free to visit it. If you have any question, feel free to let me know.
We actively bid on GNND houses for nearly a year before finally winning one. The process is slightly different by state, but for the most part, the GNND listings (http://hud1.towerauction.net/AR.htm for AR) are posted on a certain day each week, bids are due a couple days later, and if more than one person bids on a property, there is a lottery to randomly select a winner. If you go to the link and there are no properties available, try again every day for a week- the "no available properties" message often is put up after the bid deadline for the week, and before the new ones are posted. For example, here in CO there are no listings from Tues to Thurs (new properties are posted on Fridays, bids are due Monday.