Oh yes, females spray! Check out the thread entitled "Help! Pee Pee War" in this section to see what I'm talking about.

But, never fear! It really does take a little while for your fuzzy female's horomones to calm down after surgery, and remember that she was an adult (who had already experienced being heat) at the time of surgery, so give her a little EXTRA time to "change" those old habits.
The two females that we talked about in the "Pee Pee War" saga have both been spayed, one as an adult (like yours), and one at aprox. 8 months old. Both have been with us for at least 4 years and began spraying about 2 years ago, simply because they have grown to DESPISE each other.
Try some Feliway (get it at Petsmart) to help reinforce your kitty's "positive marking" (face rubbing) instead of spraying. If it is just a bad habit & not a problem (like mine), it should really help! Good luck!