I've always used the moleskine weekly notebook; comes in 3 sizes, hard or soft bound, and variety of colors. http://www.moleskine.com/us/collections/model/product/12-months-weekly-notebook-black-soft-cover-large
You can get them via calendar year (Jan-Dec) or 18 month. I really like the large size; but all size are laid out with the calendar (Monday-Sunday) on the left side, while the right side is a simple ruled page (where I keep my to-do list, track other things). I converted from large to pocket size when I wasn't going to school and had less things to track, but will go back to the large size for school use. Also, the binding/cover is very durable; I throw it around in my purse/backpack, and it still stays pristine. I also imagine that if I forget to bring my research notebook or something for a meeting with professor/advisor, I can always take out this notebook to take quick notes (it has extra pages at the back of the book) and still look presentable.