The Now Habit
Productivity Engineering
Mental Toughness
Do It Now
Getting Things Done
(Personally tested and recommended by the author of this web. Some links might lead to other websites.)
Procrastination is so often connected with the academic environment and students in particular, that many university counselling centres cover the topic specifically for students:
University at Buffalo
Carleton University
UIUC Counseling Center
CAPS UNC Chapel Hill
Academic Skills Center