Where do I get an extra battery for DMC-ZS3?

I am looking to purchase the Lumix DMC-ZS3 but have read that it is really difficult to find extra batteries, which is making me a bit worried now. I read alot of forums mentioning to downgrade the firmware to 1.1. But when I looked on the Panasonic website, it says the latest firmware is 1.1 (did not see 1.2) and mentioned this firmware will not work with 3rd party batteries. I looked on Panasonic's website and they did not sell extra batteries either.

The last thing I want it to be using this camera and run out of batteries!

I have a trip coming up in 2 weeks, so need something.

Thanks!