I love my mid-tech personal organizer.
It consists of an inexpensive 5.5" by 8" binder, with paper of the same dimensions. I have little tabs for each of my to-do buckets like "at computer" and "at electronics store", etc. and tabs for each month, and an insert for "today", and finally tabs for letters of the alphabet, where I keep phone numbers, addresses and contact info.
I'm even learning Gregg shorthand to be able to write in it super fast, as per David Allen's suggestion to learn typing. (I already type super fast, but it made me realize that my handwriting speed is insanely slow compared to my Dvorak typing speed at the computer.)
What I'm still looking for:
-A good quality and affordable 3-hole punch for 5.5" by 8" paper
-Durable (plastic?) holed 5.5" by 8" divider sheets that have slidable tabs. Like some sort of mechanism where you can click something then slide the tab sticking out up or down. So if I add a new "bucket" for "at library" between two others, I can quickly add a tab for there and then move the others down so they stagger and cascade perfectly and alphabetically.
I guess the closest thing I can think of is to use A to Z tabs, and then within them have some sort of sub-tabbing system that is easier to remake from scratch if I need to move categories or add some.