I go pretty simple. Just a binder clip. In the early days, I took a lot more info than I do now. But, I would have
1) a typed itinerary-one page for each day so too much info doesn't get garbled up- this wasn't our "what to ride info" but our "where to be info". I'd have which park, it's hours, any EMH info on it (and I've have other parks info--smaller but still readily available for a last minute change), any dining info, might put some little-known park info here, etc. etc. This made for one concrete place to gather info in the months prior to the trip.
2) one page of helpful phone numbers, dining, resort, lost and found, etc. etc.
3) one page of only ressie info and all confirmation numbers, airline, rental car/ME, hotel, resort. This would indicate all times and ALL phone numbers for everyone. Again one concrete place to refer to when **** hits the fan.
4) printouts from Steve Soares site for show times, etc.
5) photocopies of the touring guide park maps out of the back of UG (always kept pages intact and not written on so I could resell on ebay)--on these I would highlight one color to indicate which offered FP, and another color if height restrictions were an issue for us. On the back of this I would write the park hours for the day, any dining ADR info, show time info from SS, any Dis tidbit info I'd learned and might forget, what my top 3 CS choices might be, and maybe a list of our top 5 things we want to accomplish that day (helps maintain the focus).
This photocopy is what I would fold up and carry in my pocket, it was more useful to me than the park map.
6) Photocopies of things that would kill you if you lost. Some of these I only left at home with family, but would include photo id (especially usefull when flying--don't ask me how I know

), credit cards (helpful to have numbers to call in lost/stolen--but I usually keep with family), and park ticket backs--also good if lost.
7) This whole packet would be given in it's entirety to someone back home that I could call to get the info should my copy get lost or destroyed.
On the return is when I move to the fold-up binder system for longer term storage of the park maps and show times guides, resort maps, etc. etc. from our trip that I can share with others during their planning.
Hope this helps
Happy planning