If the tools are pnuematic, Cleco and most of the companies that manufacture tools make sleeves suitable for the tools. Prices are typically $3-$4 each. From experience they function very well for the application. However, the operators tend to not like them because of bulk. With pistol grip tools we have found the various gel palmed gloves to be a better alternative from the operators point of view. Straight drivers tend to be okay with the foam sleeve.
We have tried numerous examples of the add-on tapes, padding, rubber, etc. and have found none to be as useful as the above. I currently have about 100 operators using the gloves and 250 using the foam sleeves.
Just as an aside, the most important factor in finding an antivibration padding has been operator acceptance. It's just one of the psychological problems they forgot to mention in school!
Good luck finding the right solution for you.
John C.