I have an HMC-150 and use Premiere Pro CS4 and I do not understand how to drop different frame rates into different time lines. I usually shoot 720 60p and just change the speed and duration. How is that different than dropping 60p into a 30p timeline (whatever that means)? Again, sorry for the newbie question, but I'm new.

If you put 60p into a 30p tilmeline, your program will blend frames together to conform the footage to fit the timeline. Which isn't really what you want. It's better to edit 60p on a 60p timeline.

Or, if you're going for the slow-mo effect, you can drop 60p onto a 30p timeline, but you'll have to tell the 60p footage to play back at half-speed.