Some sample audios for IELTS practice are available at Oxford University Press website. You can download them from here:
http://www.oup.com/elt/global/products/ielts/masterclass/a_practice_test/

One useful sample file is available here too:
http://www.ielts-worldwide.com/ielts-example.htm

I've found an IELTS listening practice website. Though it doesn't provide MP3 files to download, you can listen to audio clips online and answer the questions asked there. I think it is the best way to practice for IELTS listening section.

Here is link to IELTS listening practice page:
http://www.examenglish.com/IELTS/cbIELTS_listening.htm

You can find over 10 hours of IELTS listening courses once you register on http://www.expressteach.com/ - you can listen to the MP3's online, and as you listen to them you can answer the questions online and get instant feedback to your answers.

Try it out!

Here I have listed the link where you can download MP3 files of IELTS listening for free-

http://www.ielts.org/test_takers_information/test_sample.aspx