I LOVE the Franklin Covey system for organizing your business/life. I attended a seminar years ago and part of the seminar was the Classic Day Planning system (daily). I have continued to buy the refills year after year because I love this system. You can buy the undates pages and date yourself or buy a year at a time (starting any month you wish). It's a very easy system to use, organizes your day to a tee. I personally like the DAILY system, but you can also purchase weekly and monthly. I'm very anal-retentive and like writing down and checking off everything I do. If that's not your thing, the weekly will do for you.
Franklin Covey systems can be purchased in many sizes. Classic is the average size, there is also a pocketbook sized one as well as a larger one. You can purchase in many places, though the Franklin Covey store and website have the best/largest selection. I have seen their products at most major office supply stores as well as the "big box" stores like Target and Wal-Mart.