J.S.
You are a very generous person! I have NEVER heard of a buyer giving a realtor a gift - they make 4% (I think that is the percentage) of the selling price of your home. I have owned 4 homes, and each time, the realtor has given us a gift at the closing. (an address stamp, a silver platter, etc.)
I don't want to discourage your generosity, but I think that the best thing you could give her is a card expressing your gratitude and telling her that you will give a strong personal referral to anyone you hear who needs a realtor. Perhaps even write a letter to the agency she works for, telling them what a great job she did and (since she is new) that she is a great addition to their team. Congrats on your new home!