Useful links about IELTS
Here are some useful websites for you:
For general information, a sample test, test dates and test centres near you, go here
For which bodies require IELTS, booking a test and IELTS preparation, go here
For exam format, preparation and exam dates, go here
And some good books:
Cambridge IELTS Practice Tests (1-8)
Objective IELTS Advanced Self-Study
Objective IELTS Intermediate Self-Study
Action Plan for IELTS Self-Study Academic Module
Action Plan for IELTS Self-Study General Training Module
Cambridge Vocabulary for IELTS
Cambridge Common Mistakes at IELTS Intermediate and Advanced