I've joined forces with the hobbyDB team to create a database of every Starbucks Mug ever made! You can use hobbyDB to manage your collection and wish list, show it off, find values for your mugs, and to trade, buy and sell. We currently have four volunteers and would love to have more join the team. If you'd like to help, contact the guys at hobbyDB.
I just returned from a 5,185 mile road trip in the U.S. with a goal of adding to my city mug collection along the way but was disappointed that none of the major cities carried them. I hope I have better luck on my upcoming trip to England, Scotland and Ireland.