Salam,
This is a very good site on which you can find some useful online tests for the IELTS
(International English l-a-n-g-u-a-g-e Testing System)
https://elc.polyu.edu.hk/ielts
The sound tracks may require you to browse using IE or Firefox, I tried Chrome and there was a problem in the media player plugin .
Apparently ,the site is hosted in Hong Kong on the polytechnique institute's server and therefore you might experience some delay in connection depending on your ISP speed.
All the best in your exams
Wassalam
Abbas