This is probably an over-generalization but I would say that you should expect to pay the same amount as you would for stuff in Orlando, but in Canadian dollars rather than U.S. currency. Therefore, everything should be a little cheaper because the Canadian dollar is worth around 80 cents of U.S. currency.
However, you should also know that there are two levels of tax on most purchases (8% provincial, 7% federal for a total of 15%). The federal level of tax may be recoverable by tourists by mailing in for a rebate but I think that some sort of stamp needs to be obtained on the supporting invoices before you leave the country...so, make sure you get the details about this as soon as you come into the country...you should be able to get an explanatory brochure at the border from Canadian customs.