I had all my paperwork and taxes done and was all ready to pay the $150 to get a temporary sellers permit and the customs officer asked “Do you  have your letter?” and I got all flustered. “Um, my Canadian friends are in the airport to pick me up. I can get them to write me a letter of recommendation?” But it turns out that you just need a letter from wherever you’re going to work so that they know that you’re really going to work there. I had an e-mail from the convention detailing the specific legal chapters that we were applying for. The customs officer said that the e-mail was fine or even my name listed on the exhibitor section of the Calgary Expo would do.
I got totally into eavesdropping on the other guy though. I saw a business man going into another back room when I walked up to the counter and I listened while another customs officer called someone and this conversation took place. So apparently, if you’re not a nice person, you can’t get into Canada.