I gotta say first off I do feel like a giant information mooch on this list.  I wish I had something to offer for all the great advice given on a daily basis.  

So I pulled the cover off the van 2 weeks ago and asked it to pick up a corner hutch for me.  I couldn't help but notice that the solid oak cabinet attenuated a lot, I mean a whole lot of the engine noise.  This has encouraged me to pursue some type of effort at sound dampening the engine bay area.  Hauling around the cabinet won't work very well during the camping season.  

Archive searches have turned up either using heavy carpet or some form of "dynamat".  I thought I'd ask a targeted question to y'all before acting on this.  I was wondering if a acoustical dampening carpet pad existed for commercial or residential carpeting.  I did call a carpet place and the guy answering wasn't very helpful.

What have you used to dampen the sound from the engine bay?  How effective was it?

On a related note my muffler/tailpipe is going to be replaced, the existing unit is a one piece deal.  Can expect any decrease in engine noise with a new (OEM style) muffler?
Is Bus Depot the best practical lower cost solution?  

Thanks for any and all help....

Ryan