The first things you probably think of when you hear "Columbo" are a cigar and head scratching. How can this have anything to do with Apologetics?
I was encouraged by this video posted on another blog.
Greg Koukl: Christianity Worth Thinking About, Part 1 - "Columbo" from Metropolitan Bible Church on Vimeo.
His website is here with more information.
And he also has a book. I have not read it, but from the reviews, his talk seems to mirror the content of the book.
I would encourage you to play the movie and listen to it as you are working on mondane tasks. The strength of the video is found in his use of questions to open up conversations, and seek to "put a stone in your shoe."He encourages the listener to "go on the offensive in an inoffensive way by using carefully selected questions to productively advance the conversation."
He doesn't stress continued follow up, which I think is a weakness.