You need to fill in the purple (I think it's purple) slip on the logbook - it's the third one down on the inside right-hand page and send it to DVLA (only send the little slip - keep the rest).
This will let them know it's been exported, so they don't chase you for renewal of Road Tax / SORN (you'll also get fined if you don't let them know).
Take the rest of the logbook with you to Albania, together with any other paperwork you have, and ask there how to go about registering the vehicle.