There are no free ones that are trustworthy. Tor isn't the worst suggestion, but you have no control over what country you'll pop out of, and you would have the same, or different problems as a result. Also the bandwidth is shoddy.
If you're just going around an IP restriction, Amazon Web Services offers an effectively free server in either the US or Europe. After the first year, they charge by the hour, as a matter of US cents. If you're willing to learn how to run a barebones server, you can use it as a simple proxy for your browser (but traffic and requests will still be unencrypted). On the other hand, an SSH tunnel to that server will effectively do the same job your VPN would, and encrypt the traffic. Even better, an SSH connection is far less suspicious than a VPN or Tor, and if you run a small webserver on the Amazon instance, you have an excuse as well for connecting in the first place.
All this sounds more complicated than it really is. See aws.amazon.com for the details. To set up a temporary socks proxy to the server (if ssh is set up, which any linux or unix-based server comes with by default), you just run something like
ssh -D 9999 your.server.ip.or.dns
...and configure your browser settings to use the socks proxy on localhost, port 9999 (though instructions will vary if you're using windows; you'll need cygwin running for this to work in that case).
When you're not using the micro instance, shut it down, or it will cost you as much as $18/mo to leave it running after the first year. If you only turn it on when you need it, the charge is something like $0.014/hr. (edited to correct- yes, that's less than two cents per hour)