Do you have any guidelines? White or Red? Particular varietals or styles she enjoys?
Otherwise I'd go to a legit wine store in your area and just talk to a salesperson - kinda hard to give recommendations with nothing to go on.
If you have time to order online, a friend of mine got a case and split it up amongst us of this:
http://2020wines.com/2006-shirvingto...224_f0111_0856
And it's fucking fantastic. Retails for $60 most places, but you can get it for $30/bottle here. If they like Syrah/Shiraz, I don't think you can go wrong with this. I got 3 bottles, drank one a couple weeks ago and am trying to figure out when to drink the other two. All my friends that have tried it really liked it as well, an truly exceptional wine for $30 (considering it normally retails at double that). 95 points in Wine Advocate is serious business, and for that price for a McClaren Vale - yeah, do that unless you know she doesn't like reds/Shiraz.