to be honest i think your over paniking, if you got paperwork, mots and history etc i wouldnt panic so much, like matey says above hes prob not answering calls cause thinks your phoneing up for a winge
walk into the police station state you just bought a car with no logbok etc and are suspicious, give thm the reg and chassis i net your arse they will check it out for ya, i dont it in the past when i used to collect scrap cars to weigh in etc
dont panic no logbook doesnt allways mean stolen