It looks like your message is lacking a beginning! I will write it for you:
Finally, a free software is able to extract RARv3 archives ( http://www.fsf.org/blogs/licensing/free-rarv3-extraction ). It is named TheUnarchiver and can be compiled on Trisquel GNU/Linux. To do so, download the source code (behind this link: http://theunarchiver.googlecode.com/files/TheUnarchiver2.7.1_src.zip ), uncompress it (for instance right-clicking and choosing "Extract here"), open a terminal... and follow the instructions above!
