You can use pool.com,snapnames.com, namewinner.com, godaddy.com just to name a few. Most charge $60.00 to try to obtain the domain. If they do then the domain go's to auction. If no one else bids on the domain then you will own it. If others have back ordered it then it will go to the highest bidder.
If a domain is not obtained for you then they charge nothing. Hope this helped a little.