One of the most important things you can have during a move is a notebook. I prefer mine to be pretty.
In this notebook, I keep a running to-do list. Things like "mail forwarding with Post Office" and "mail deposit for new water company." It is also where I list all the utilities and services I am starting or canceling, their phone number, my account number, and any other important information. This way, if the cable guy does not show up on the appointed day to install my service, I have all the contact information in one place. I will also use it temporarily as an address book, especially at the new home where I may get a few suggestions for a piano teacher or a babysitter and I need to call around until I settle on someone who will go in my more permanent address book.
And then, those last days at the old home, I have handy sheets of paper where I can scribble notes to people to leave on doorsteps: "Thanks for loaning me this book. Sorry I missed you. See you in two years."
Next you need a big, zippered envelope. This holds all of your PCS related paperwork: receipts, the papers the movers give you, the papers the transportation office gives you, half a dozen copies of hubby's orders.
I also have this small, portable filing bin that I use all the time. This is the last thing I would remember in a fire, but the first thing I would wish I had grabbed. It contains the most important documents: birth certificates, marriage certificate, passports, kids' immunization records and their most recent physicals, dog's shot records, our mortgage, rental agreements, social security cards, and similar papers. We have other filing bins that we let the packers wrap up and the movers transport, but this filing bin goes in our car.
Lastly, I will keep my address books with me. Someday, I will have all that information in electronic form, like on my iTouch or in my cell phone. But for now, the old fashioned kind is all I have. I must admit that I do not have my parents' home phone number memorized. They relocated to Florida after the invention of speed dial, and I have never forced myself to learn it. However, they are probably the first people I might call with a question like, "Mom, can you google the phone number for the cable company that I forgot to write down in my notebook?"
Friends and family are always a good backup for a missing brain.