You can find more info about applying for a B2 visa here: http://travel.state.gov/content/visas/english/visit/visitor.html#overview
Actually, having PR in a different country will not have any negative effect on your B2 visa application (no matter how new the PR is). Depending which country you are coming from (your passport), you can get a 10 year multiple entry visa.
If you received your Canadian PR though spousal sponsorship, meaning your spouse/common law is a Canadian citizen or PR, this will most likely show enough ties to Canada to convince them you will not overstay your US visa.
"Evidence of your employment and/ or your family ties may be sufficient to show the purpose of your trip and your intent to return to your home country." - quote from the website I posted.
@ Awesomeg: I believe you are incorrect. It doesn't matter if you are a new immigrant to Canada as long as you can show enough ties to that country - and generally a spouse/family is a pretty strong tie. Who would go through Canadian PR sponsorship just to go to US and overstay their visitor's visa? If more than anything, having gone through the proper immigration channels to arrive in Canada, shows that the person is obeying immigration laws - which is a good sign that they will not overstay their visa.