depends if you just buy the core, which is JUST the system no controllers, NOTHING else, and that is 299, where the Xbox with everything is going to be 399 (thats US prices) add your [url=http://www.taxlaws.org]tax[/url] and you get your total
FOR CANADIANS
well since i don't know the price on a US doller, i'll ASSUME it's 1.50 to our doller
Core: 299 round to 300 (XBOX 360 price) + 150 (Exchange rate at 1.50 $) = 450 + 15% [url=http://www.salestax.net]sales tax[/url] = 517.5, round to 518$ (just a brief estimate)
Packaged Xbox = 399, round to 400 + 200 = 600 * 15% = 690$
Core = 518
Xbox = 690 (my recommendation, is to get this one..., with everything that is included)