I'm throughly addicted to audio tours of places, be they buildings, city districts or road tours. The first one that I came across several years ago was Invisible5.

"Invisible-5 is a self-guided critical audio tour along Interstate 5 between San Francisco and Los Angeles. It uses the format of a museum audio tour to guide the listener along the highway landscape. "

In terms of libraries, audio tours have mixed results. Some are just too lame. One better example is:

Ohio University Libraries

When it comes to buildings I want a video tour, short clips about different places on the tour. I want my students to make a tour for the library this way. Each group is responsible to produce a different segment of the tour. I'll string it all together...