Where the log book?

Hi, i purchased a car off a work mate, we filled out his log book and sent it off. then i got a reply saying it need to go for a test befor we can give you logbook, so i tuck it for the test it ped, then i forgot to send for a the log book and the paper saying that it had ped it been about 8 monthsm, now i have sent the information about 2weeks ago and yet still not recived it, so does any body know how long it will take? cuz i need to tax it its just sittin there