There's a number of websites out there that list Anonymous Proxies that you can use from all over the world. I wrote a perl script that will go to a number of these sites and parse out the proxy information for my own use. Here's a few of those sites though:
http://www.proxy4free.com
http://www.stayinvisible.com
http://www.findproxy.com
http://www.freepublicproxies.com
http://www.publicproxyservers.com