Here's where I originally saw this stuff. We get this catalog at home.

Muesuem putty

Also, if you do a search on Google for "Museum Putty" there were a ton of hits. To find it locally, you might want to try like an Ace Hardware or similar. Don't know if Home Depot type places would have it, and even if they did how would you find it in a place that huge?

I thought it was interesting on one of the sites I found through Google, they used the stuff as a "Baby Proofer." If this stuff makes your valuables "baby" proof, they must surely be "cat" proof, don't you think?