I don't really know, it'd be hard to guess without playing you :) -- at 1100 if your opponent started without their queen I'd guess 1400-1500 range... USCF... not this site's ratings, I'm not sure how strong each level is here.
To beat a grandmaster? With that much material off the board it would just depend on how attentive you are, as long as you didn't hang any pieces (leave them undefended and give them up for nothing) you should win. But because you only picked up chess a month ago that may or may not be possible 
As I continue to get demolished by Chessmaster I had a random thought that you guys could answer. I'm a newbie. I picked up chess earlier this month for the first time and I sit around a 1100.
My question is this. If someone at my level took my opponents queen of the board before the start of the match what rating level would I be expected to beat? And to carry that, would I be expected to beat a grandmaster if I took his Queen, Rook and one minor piece away before the start of the match?
Just something I was contemplating.