New to carving...
Depends on a couple things: experience on a board and if she is more timid or aggressive at skiing/boarding.
Complete beginner and wanting a gentle introduction, get something like a Donek Pilot or an older Burton Alp. Keep the length short < 160 cm so it is easier to manage. Avoid slalom decks (under 10m turn radius) that force her to change edges too fast. Many older and cheaper decks are short (Rossi, Burton, Sims). Alot of short, older boards end up on the bay.
If she is already good on a freestyle board and will likely progress quickly at carving, get something a little stiffer Donek FC or older Oxygen Proton, Burton Ultra Prime.
The Donek Pilot is a great choice either way; it is well built and current. The board is more forgiving and well suited for light-weights. Most other current makes are too stiff for lighter riders. They are $375 brand new from Bomber.
http://www.bomberonline.com/store/boards/donek_pilot.cfm
You can get an older board like an Alp for $100 or less. There are not many shorter decks on Bomber right now. I am looking for similar gear for my wife but in the advanced category and a little longer.
Rossi Race 156
http://www.bomberonline.com/VBulletin/showthread.php?t=19469
Another Rossi
http://www.bomberonline.com/VBulletin/showthread.php?t=19216
Oxygen Proton 149 - shorter but more advanced
http://www.bomberonline.com/VBulletin/showthread.php?t=18934
Burton Alp - but it is 164
http://www.bomberonline.com/VBulletin/showthread.php?t=18657