Loving the new Ihnatko Almanac show… just listened to episode 00007 and wanted to pass on a couple of other great detective shows in the vein of Columbo… both are BBC shows, so they are long format and very interesting acting.
1) Foyles War http://www.foyleswar.com/ This is a historical detective show taking place during WWII in England. Great blending of the history of the war as it was seen in England with the type of detective you will love.
2) A Touch of Frost http://en.wikipedia.org/wiki/A_Touch_of_Frost_(TV_series) Current (well it was in 1992) series (actually going through 2010) again with long form, yet connected characters and stories.
Foyle's War is not available instantly from Netflix, but it is from Amazon Prime. A Touch of Frost is available from Netflix streaming.
Sorry about the strange way of communicating, but I couldn't find an email address for you and had to much to say for just a tweet!