Thomas Westin @ DSV

Premiere Pro CS3 users have noted the lack of AVCHD support, available in other tools like Final Cut 6 and Sony Vega.

While there are third-party plugins for Premiere they are expensive

Here are three links to solutions for free / cheap conversion paths

For MacOSX Intel, iMovie08 supports AVCHD. Included in iLife for 79 USD.

For Windows, free 30 day trial, read/writes AVCHD directly:
Sony Vegas Pro

For Mac and Windows, 30 USD VoltaicHD