hpi wont tell you the current owners details, if you use the AA you can tell them the current owners details and they will verify them but will not tell you over the phone, but as you dont have the V5 there they will tell you they cannot guarantee any of the info. To apply for a logbook you need form V62, fill it out and send it away there shouldnt be any problems. If its a big deal tell the current owner to phone the DVLA and ask them to send a copy of their V5 to them. Since they are the current owner it should only take 3-5 working days. Then you know for def. Thats what i did just before i sold my bike a few weeks ago, took 4 days for it to arrive and i think it was free??? Maybe a fiver/tenner but not alot.....