Thanks for all the tips.
I did buy my regular external hard drive for the MacBook Pro yesterday. It is a WD 1 TB triple interface (2 500Gb) and I plan to format it for HFS+ I don't do much HD yet so I felt this would be a really great way to learn FCP 6. I have a personal short project I shot in PA last weekend in HDV and it doesn't have a deadline. But the issue here is to be able to transport mov files from a MAC FCP project over to the PC for additional work in Vegas. Working with both I have found that Vegas is soooo much faster, even with FCP captured mov files than rendering in FCP. But it doesn't look like I'll be able to easily do what I want uinless these 3rd party tools you described can work.
I was planning on posting another thread about the network drives to see if anyone has any experience with them. I have one application that I need to access the data from several computers and keeping the data on one computer with a backup drive has proven to be loaded with hidden errors. While applications like this would work great with a network drive, I doubt my video work will due to the speed of the network. Mac people are saying they want to see a firewire 800 drive for HD work. That's why I went with that type of drive.
From what I saw at NAB FCP6 works very well with HD as opposed to Vegas which can't play the timeline in real time without hesitation. Then once the project is edited, with FCP, I can just let it render, for days if necessary and it won't hold up my other SD work. It's always a balance of what tools work best in each case. Neither is perfect for all tasks.