I did this a year ago, we found a template offer contract online somwhere (don't remember where) and changed what we wanted to. Then we went to a title company that did all the paperwork for us.. cost about $6k closing. Just search (phone book?) for title companies.

realtors don't do anything at the closing, the title company does all the work. Supposedly you can do the closing yourself without a title company, bringing the closing costs down to less than $500.. but I didn't do enough research into how that works.