I am not a lawyer. So take this as it's given - in good faith, but as something you should verify via other sources, i.e., an immigration lawyer or the Canadian consulate nearest to your home.
Visas aren't required to enter the US as a tourist from Canada. Normally, a Canadian can enter the US and stay, I believe, for six months, before having to leave.
However, this is an unusual circumstance. Are you saying she got married in October, 2011, after entering the US in September, 2011? If so - then although she entered as a tourist (thus no visa), she is not here as a tourist - she does not plan to return to her home in Canada. She got married and plans to stay in the US. She should have entered the US on a K-1 fiance visa. This is a non-immigrant visa.
http://vancouver.usconsulate.gov/vis...nce-visas.html Once she'd entered the US and gotten married, her husband would then file the appropriate paperwork to allow her to stay.
But that's not what happened, and it'll be quite clear to US Immigration that, based on the timing of her entry in to the US and then her marriage, she entered the US with the express purpose of marrying a US citizen and remaining in the US, and not as a tourist - thus she needed a visa. I am thinking that this could potentially be a major issue. I don't know what happens next. You may want to consult with a good immigration lawyer, very quickly. She may also want to seek advice from the nearest Canadian consulate in the US, very quickly. She needs to find out if it is it possible for her to stay now, and get this resolved. If not, can she return to Canada, file whatever paperwork is required, then return?