Quebec does not refund the 7.5% PST, or Provincial Sales Tax. As of now, in order to qualify for a GST refund, one must spend a minimum of CAD$200. HOWEVER, each receipt you sumbit must be a minimum of CAD$50 BEFORE TAXES!! Also, there is no refund available on fuels or meals, but hotel rooms do count. Other than that, any goods that you are claiming GST refund for have to be with you when leaving Canada. If you do not meet the CAD$200 minimum, you can save your receipts and combine them with those from another trip. They are valid for one year. Remember to have the receipts for any goods being exported out of Canada stamped by Customs Canada. This is especially true if you are mailing in your GST refund and not applying for it on the spot at a Duty-Free shop at the border.
Unfortunately, it seems that the GST rebate programme is scheduled to be no more effective 1st April, 2007. Thus, no GST refund will be available for goods, services, and accomodations purchased during the Fest. =( (Sometimes you loathe what you find when you do a google search to get more info) There is rumor that this programme might be extended. We will update if any changes come about.