You can get Columbo - Series 1 (Box Set) for only £9.95 delivered from dvd.co.uk - the cheapest I can see elsewhere for this is about £16 @ amazon, so that's a pretty good price!! (EDIT - Now down to £7.95...)
I used to love this show when I was younger, when Columbo knew who the killer was as soon as he laid eyes on them, and just needed a modicum of evidence to make them confess!!!
Details: The entire first series of investigations featured Peter Falk's now classic deptiction of crumpled trenchcoat-clad detective Columbo. Also features the pilot movies Prescription: Murder and Ransom For A Dead Man