I did it a couple months back on a Tourist Visa in Chiang Mai. I needed a confirmiation of residency form. You used to be able to get it at the Chiang Mai immigration office (near the airport) for about 40 baht, when I attempted however they had at that time stopped the issuance of those forms for Tourist Visas. I then went to my consulate (U.S.) where for 1200 baht they issued one without any verification of my address.
Then it was off to the Thai Motor vehicle office where you filled out a multitude of other forms to complete the transfer. Have with you copies of the sellers I.D. along with their signature indicating a release of the vehicle. The deparment will take rubbings of the Vehicle ID numbers and then you turn the completed forms into the Department.
The next day I picked up a new Green book issued in my name.
Word of warning. If you cannot speak Thai take someone with you who can to sort out the paperwork at the Motor Vehicle office.
That was my experience in Chiang Mai. Here's hoping its of some use to you. Good luck.