Unless you're also a US citizen, you're going to need a work visa. Being a Canadian PR (or even a Canadian citizen) by itself doesn't exempt you from having to obtain a visa to work in the US.
It's not that simple, you still need a visa. The difference is that under NAFTA, you can get a TN (?) visa which is a lot cheaper/easier to get than a H visa, but as such, it's more restricted than H (Can't apply for PR under NAFTA visa).