When it comes to money and taxes, my advice it to bite the bullet and talk to a US accounant or tax lawyer -- I don't know about accountants, but you should be able to find a lawyer to give you a free consultation. You don't want to get cught being reassessed in a couple of years to find you owe a bunch of back taxes plus interest after you've spent the money.
(It's been a while since my international tax course, so take the following with a grain of salt!!)
Regarding your gift, in both the US and Canada, you're taxed on all of your income in your jurisdiction of residence
no matter where in the world it is earned. However, in countries that have tax treaties, such as Canada and the US, you're essentially excused from taxes by your residential government for income earned in the other jurisdiction, but usually based on the policy that it will be taxed by the jurisdiction where it is earned.
In the US, unlike Canada, I'm pretty sure you're taxed on money received as a gift, so under the principle of you being taxed on all of your income in your jurisdiction of residence, you'd technically owe taxes on that gift from your parents to the US gov't. Is it exempted by the treaty because the gift occured in Canada even though it's not taxed in Canada? I'm not sure. I'd definitely want to find out if I were you.
Edit: I just found the following on an
IRS site:
If you gave any one person gifts in 2007 that are valued at more than $12,000, you must report the total gifts to the Internal Revenue Service and may have to pay tax on the gifts. The person who receives your gift does not have to report the gift to the IRS or pay gift or income tax on its value.
So that should reassure you about any gift taxes, but does re-enforce the fact that Tax professionals really are he only ones to take advice from!!!