Who makes a "true" Transmission Line speaker?...

Take a look at Meadowlark Audio... there are some cross sections of speakers in photos on the website as well as Pat McGinty's philosophy on speakers and such...

http://www.meadowlarkaudio.com

Off the top of my head(in alphabetical order), Bugtussel, Fried, Meadowlark, and PMC.

The Bugtussels look attractive, though I wonder about the cheap looking tweeters. I need to give them a listen. Yesterday was a good opportunity, as I was around a bunch of them, but we only listened to the Von Schweikerts and Ushers. Fried, which I am a part of, is releasing a real TL right about now. I have heard it, and it is a very open, clear sounding speaker. While I have not heard the big Meadowlarks(would like to), the weak kneed bass of the smaller ones make me wonder why they even bother. PMC speakers seem interesting, and probably offer the real deal.

Pat McGinty is a great designer. His speakers are well built and easy to drive. Meadowlarks are worth a listen.