Dynamat's a ripoff, it's just some rubberized asphalt with a backing that you can get at a lot of places. Try some stuff called raamat. It's what i used and is identical to dynamat extreme. It's actually a little bit thicker so works even better. My friend that did his whole truck in extreme felt like an idiot when i showed him the raamat stuff for like 1/10 the price.
search ebay for it. if you live in a northern state you could go to home depot and find some stuff in the insulation section that is just like dynamat too. Forget what it's called but it comes on a roll and only is sold in states with a lot of snow.
