Dynamat is popular with Car Stereo installers.
Mike Powell of Verastarr.com sells what you ask about. His product is named Starrdamp, and one side of it is copper which also shields from RFI.
He is currently having a closeout on his mass loading granite blocks which are another aspect of tuning and clarifying.
I have used both of his products in a few of my systems with fine audible improvement.
Herbie's Audio Lab also has great products which you can read about on Herbiesaudiolab.com. I use in a few of my systems and the product line is extremely broad, and addictive.
Both sites list phone contact numbers to speak with the owner. ("Herbie" is a nom de plume) Both are dedicated audiophiles who spend time with a caller.
I don't think this will do what you want, but it is so inexpensive, you ought to look at it. At the local hardware store, you can buy sorbathane peforated mats, which go in your kitchen drawers and cabinents to keep things from sliding around. They are very flexible and come in rolls and are very inexpensive.
Stack them up, layer by layer, to kill any vibration you want to kill. Cheap and works great.
The only catch is, they aren't adhesive, so if you want to keep your chassis from vibrating, it won't do the job.
Partsexpress.com has great selection and sizes, and they are speaker and home audio based sheets for the actual purpose, used in many hi-end components, they also carry dynamat with the metal backing that I found very good as well, but you could just go to best buy and get that, it is all very cheap from parts express however at about 1.50 10" X 10" sheet.
The reason for asking this question to begin with was because I can feel cabinet vibrations along with the music in my CDP and preamp when I place my hand (palm) on top of the components. I figured dampening sheets would help this. Then, I remembered I had three isolation cones in a spare drawer. Sunday, just for the heck of it I placed them beneath my CDP. Like I said above, before the isolation cones, I could put my hand on the top of my CDP and feel the vibration of the sheet metal with the beat of the music. After I put the cones on the CDP, it was greatly reduced, say, 90%. I'm wondering if the coupling I'm getting from the cones is all I need? Regarding the sound, I can say I never associated my component vibrations with sound, but I knew the vibration in my CDP couldn't be a good thing. After the cones were put beneath my CDP, the vibration is tremendously reduced, but not like a night/day difference. I want to say my system sounds more focussed, but I'm not sure if its because I want it to or because it actually is. Any thoughts?
Mijknarf, A very tiny cost further upgrade to your cones would be to add dampening using herbiesaudiolab.com Grungebuster Dot between the top of each cone and the flat component chassis undersurface. For a microscopic price, there will be more clearly audible upgrade.
Also, sometimes, placing Audiopoints APCD2 Coupling Disc to receive the sharp point of the cone increases the sonic benefit due to a proprietary design to sink the vibration energy even though the point is no longer directly contacting the underlying shelf.
If you call the telephone number of Herbie's Audio Lab you can get an entire course in how to dampen everything in sight since there is more to know than what I briefly touched upon.