I've used the same type of running journal three years in a row because it's just that good! First, there's a monthly page where I pencil in the workouts I want to do (lower right). Then when my workout is done, I use my four colored ink pen to write down what I did (top right). Blue is for running. Green is for other exercises. Red is for problems. Black is for anything else.
It's a 19 month planner, but I cut some pages out and make it a 12 month book, leaving a few extra pages behind to write extra information, like detailed marathon reports and how many miles I've put on my shoes. I found it with the school supplies at Walmart for just $4. The planner is made by Carolina Pad and you can find it at other stores listed on their website.
And now to today's workout... After a short abs workout, I ran eight miles. The temperature was about 80*F and I drank Gatorade every two miles. I felt a little tired in the last two miles, but I was able to keep the pace up so I wasn't too bad after all. Today's average pace was 9:30/mile.
Pre-run: English muffin and PB & J
Post-run: chocolate milk and strawberry Luna bar