How to do research / write a thesis / publish a paper
My system of work (not!) by Avinash Dixit
How to build an economic model by Hal Varian
A PhD thesis without tears by John Creedy
Writing Tips for PhD students by J.H. Cochrane
The young person's guide to writing economic theory by W. Thomson
How to write in Economics by P. Dudenhefer
How to publish in top journals by Kwan Choi
On a personal note:
I find the little book by Strunk, W., E.B. White, The Elements of Style, Boston: Allyn and Bacon one of the great resources for clear writing.
One of the perfectly written books, to my point of view, is: Debreu, G. (1959), Theory of Value, New York: Wiley.