where to find 3M Damping sheets?

Anyone know of a source of 3M's constrained-layer damping sheets?

You might try Michael Percy Audio .

I know he carries a number of hard-to-find damping sheet products, but I'm not certain about the 3M sheets. Presently, the bandwidth on his website has been exceeded, so it won't load. However, if you view a cached version of his contact page you will see an email address at the bottom.
Thanks, Tvad. Actually I just found them at Music Direct although I couldn't find them on my first search. I'll try MPA in the future to compare prices.
Auto Parts/Supply stores.
You can buy an excellent assortment of noise and vibration damping sheets from smallparts.com. Just type "damping sheet" into the search parameter. I've had good results with their products.
You might want to consider the Verastarr damping sheets. They not only provide good damping, but they provide good copper shielding as well. Here is a dealer selling it for a bargain price:


Thanks for all the advice. I'll look into all the recommendations.