Well if I was you, I wouldn't download it, even tho Limewire is improving there is still viruses and a lot of spam (not much that they can do about that) but if you want to try it here are the links for both.
Ares:http://aresgalaxy.sourceforge.net/
Limewire: www.limewire.com (after you download the free version you can try and download the pro-version, in the same free limewiere)