You can hear the police recording without all the "sign in and get SPAM" at the AMW site at catchbtk.com. The recording is a typical "911" snatch, with lots of background noise and only brief snatches of the "voice."

There are numerous websites now dedicated to this case, and "BTK" in google will get quite a lot of stuff. There's even one (or more) Russian language sites that has/have been offering guesses and opinions to the police on a fairly frequent basis.

The "poem" was published "back when" BTK was active, and is apparently a mangled "from memory" rendering of a rather obscure folk lyric. At the time, the "original" poem was published, but I have no way of digging it up now. A fairly extensive search was done for people who had taken the prof's class, and most who were still "local" were interviewed at the time. Someone who left the area shortly after taking the class might not have been interviewed, and might have something to add.

The description and history that's been published recently are reportedly what BTK says about himself, and may or may not be truthful. As additional info, it has been frequently observed that he has shown quite a lot of familiarity with police methods, so could be a member of the force or just a "follower." ("Close to trains" could even be his code for "close to cop shops." – but don't quote me.)

John