OK, it's a bit pricy, but this is NYC and you just have to experience TV and it's history, because it's what makes NYC Unique.
I've been on this tour a number of times over the years. The tour guides will take you through the current studios, mostly the ones that are not in use at the moment, and will walk you through the TV experience, showing you slices of history, memorabilia and you might even catch a glimpse of a famous personality wandering the halls!
The store is very pricy, always have been and unless you are really going the full tourist thing here, you may want to pass. But do ask at the desk for what shows may have tickets available for that day, or do yourself a favor and write ahead to your favorite show for tickets to tapings so you can emerse yourself in the full TV land experience.
A good look at TV studio land and another great NYC experience.