I've recently sold a number of effects pedals via another forum. Over half of the guys that contacted me where outside the US. I sold to a fellow in Norway and a couple to a guy in the UK. I also had interests from Canada. I know this is an international forum too. I lead a sheltered life here in Eugene, Oregon (no sales tax yet) and don't travel outside the country much. I was shocked and amazed at how much tax and duty items can have. The fellow in Norway said that for some reason gear in Norway and Australia is very expensive.
I'd be interested to hear what other members experience buying and selling has been.