Sure you can. For americans is even easier because they don't need visa to go there. You need the company who's offering you the job to apply for HRSDC approval. Once you have they have the approval you can apply for a work permit in the US. After you get to Canada, if your employer is willing to give you a permanent job offer you can apply for PR or PNP. There's a lot of information at the cic's website
www.cic.gc.caGood luck