First things first: mastering the language in which you present your research is of extraordinary importance: the delicious "Elements of Style" by W. Strunk and E.B. White is a classic work.
Test data for DB projects can be found at several locations on the web. A very useful link is to Data on the Net.
Richard Snodgrass has written a nice essay on (mostly) the joys of working in academia: Why I Like Working in Academia.
H.T. Kung has an interesting page on Useful Things to Know About Ph. D. Thesis Research.
Another very interesting source for advise is Ian Parberry's paper on How to present a paper in theoretical computer science: a speaker's guide for students.
A nice video with a lecture on "Writing with Power and Style" can be found here.
Do not dream of doing Computer Science at an international level without being at ease with the basics of complexity theory. The classical source of knowledge on this is the marvellous book by Michael R. Garey and David S. Johnson, Computers and Intractability, WH Freeman and Company, 1979. A compendium of NP approximation problems following up on Garey and Johnson is published on the web by Pierluigi Crescenzi and Viggo Kann.
Several professors at SITE have their own set of interesting advice. Here is a sample:
Zav Ives has assembled useful tips on interviewing for academic jobs.