I've used 3M rolls of double stick tape from McMaster-Carr, MC# 77185A25.
http://www.mcmaster.com/#catalog/118/3451/=irjew3$80 for a roll of tape that's 3" X 36 yards seems excessive, but I spent about an hour yesterday looking online and I couldn't find it substantially cheaper. I did find other double stick tape at eBay and various online stores, but some of the less expensive stuff is clearly not suitable - example: tape used to join rolls of paper in a large printing operation. Other tape may be good enough for your application at lower cost. I avoided any tape with a Kraft paper release. Three possibilities include carpet tape, golf grip tape, and auto accessory mounting film or tape. The latter was mentioned earlier in this thread, and I believe it's used to adhere automotive trim and even spoilers to the rear deck. It's strong stuff but not much cheaper per square inch, although sometimes available in smaller quantities at lower price.
I don't use enough double sticky tape to justify experimenting with possible replacements for the expensive tape I use very occasionally. It came up yesterday because I'm making a couple of batches of reverse laser engraved device labels for a couple of CNC machines that I'm retrofitting, but I don't make device labels commercially. The $80 roll works out to about 2 cents per square inch. From that perspective, it doesn't seem so expensive after all.