I always do this, and got it from Kevins Cycle in MA, but I'm sure its available from most of the big supply house as well. Racers Tape is another option, I'll be getting some to try. Jeff posted a link awhile back. Not cheap but looks like very good stuff.
Let us know where you end up sourcing it from. I've got brand new yellow plastics that I'm installing sans graphics on a 2004 EC300. Would love to install clear on them for protection.