@Account Closed yes I purchased a SFH at auction several months ago (just finished rehab and rented out). I found the home on Hubzu.com (home was 20 mins away from me) and since it was a REO, unoccupied, I was able to see the home with my realtor before bidding on it. Please note that some are "sight unseen / no entry".
Overall was a good experience w/Hubzu (search the BP forums for more info on this site and others like Auction or Xome.com), was able to close in 25 days (I paid all cash). There's suspicion (and I agree) that some auctions are auto bid-up by the website or another person to generate more money.
When I purchased several months ago, I had to pay flat closing costs/fees.. about $3K to Hubzu (no other realtors used so that was my only 'closing cost' besides transfer tax). Now though, I've noticed they're collecting more money (e.g. 4% of purchase) vs. a flat fee (which is what I was charged) so make sure you check out all the fees for closing, etc.
I think you can find good deals at auctions but you really need to:
(1) Know your market and what a good price really is ( as well as rehab, est ARV, etc)
(2) Be aware of ALL fees/terms up front before bidding (don't buy something and then pay a hefty fee to close)
(3) Have patience.. may take awhile to find a truly good deal
Hope this helps; good luck