Creativity Portal has quite a few resources related to writing and creativity of all sorts. This article titled "Creating a Writers Journal" by Molly J. Anderson-Childers discusses the value of keeping a Writers Workbook as a tool to to improve your writing skills.

Here's an excerpt ...

"What’s the difference between a journal and a writer’s notebook? They’re as different as apples and zebras! It is a matter of scope and subject, function and form…while a journal traditionally focuses on the daily events of one’s life, the writer’s notebook allows you to look beyond the surface events and delve into the life of the mind."

Read the whole article here.