Welcome to GTD, staley. GTD presents incredibly useful principles and habits for mastering your workflow.
You are right that there are many ways to implement the context-driven NA lists. There are quite a few people here who prefer paper lists (see topic with subject something like "The Day I Forgot My PDA"). Lots of people use Outlook, and there are many ways to use Outlook's features effectively for projects and actions.
I personally use a PDA with Life Balance software (www.llamagraphics.com), and would never go back to paper lists. I maintain some 500 actions and projects, yet the software consistently puts my most important actions in a given context right at the top of that list. It's just beautiful. Another advantage of the PDA is that I always have it with me. It's much easier and faster to check to-dos on a PDA than on a laptop. I can whip it out and check my @Errands list in 2 seconds when I'm in the car doing errands, or in a store. Life Balance, Outlook, and many other productivity apps can sync between a handheld and a laptop or desktop, providing the additional advantage of the large format of the laptop/desktop. Also, everything in the PDA is easily backed up.