...The only PRO NLE I've heard of to directly support 3D video is Sony Vegas Pro 10 which is a Windows 7 application. ( some of us Vegas Pro users were a little peeved that the majority of the version 10 upgrade was done to accomodate 3D video )
Cheapest way to buy Sony Vegas Pro is the VideoGuys.com Vegas bundle with an external Pioneer Blu-Ray burner : $500 US
I am assuming that you are talking about the AG-3DA1 and if so you can use any number of plug-ins with FCP. The least expensive is the Stereo Tool Box from Tim Dashwood. If you have the money the more expensive version is worth it. Next would be the Cineform 3D Neo. Definitely more money but also very cool stuff.
If you are talking about the new consumer camera, I think there is edit software in the box, but just know that is not going to give you full resolution HD 3D.
Hope this helps,
Jan Crittenden Livingston
Product Manager, AVCCAM, AG-3DA1, AG-AF100
Panasonic Broadcast & TV Systems