Just a word of caution, Do not enter in any personal information, credit/debit card information, or other generically important data in over a proxy. You do not know how secure every proxy is, or if it is malicious. I like to think that they are all safe and sound, but you must always practice safety habits.
Once again the site I gave you, appears safe- and the main proxy choice on that page appears the same- but once again don't enter in personal info.
Alot of network or security teams will block out specific proxies, or national proxies. So you will find that some work, and some dont. Normally ones that dont work are going to be the ones of your own language at work- hence forth, foreign language proxies will by pass the blocks.
I am sure you can figure it out from here, but again- if you need help- just ask.
"I'm choking on that four letter word, it sticks in my throat as i read the words YOU wrote..."