As I'm living in london, and with my travelcard have easy access out and about, Greg has pointed me at
http://www.sroaudiences.com/.
Standing Room Only Audiences - the company that deals with live TV show audiences.
I've signed up for their mailing list so I'll be able to see if anything cool is coming up that I want to see if I can get in to watch.
Tickets are free, which is a bonus - and as I have free access to Zone 3, all ill need to do is just keep my fingers crossed when i apply for something :-)
It has a lot of potential.