When it comes to the larger organisers, the ones that sit on a desk, I tend to prefer page-per-day or even 2-pages-per-day, but none of the layouts available commercially works properly for me. So I made my own:
The hardest part was building the Excel file that serves as the data source for the Word mailmerge. Have a look closely at the top of the left hand page: yes, those mini-calendars are dynamic and will always show the current month plus next month. The formulae that feed all those numbers are non-trivial, but in another part of the collection of odd jobs I call a career, I'm an Excel developer, so it was an interesting challenge.
Print this on a duplex laser, punch it and you have an A4 diary. Mine is A5, so I print this in duplex booklet layout and then guillotine the sheets and voila: an A5 diary, the way I want it.
Once I get file hosting sorted out and playing with Blogger, perhaps I could publish the source files, or at least a PDF. Let me know in the comments if you're interested. Also, now the heavy lifting of the Excel file is all done, developing different custom layouts in Word should be pretty easy, so let me know in the comments if there's a layout you've always wanted. No promises, but I might be able to produce something that works for you.