If you want to hide your IP, either get a VPN, or a 1-5 pack of private proxies. Both options will only be around $10 a month or less, and you'll be covered. If you're trying to fool a strong site then a VPN might be a safer bet, but any private proxies you buy are going to be fully anonymous as well. The problem with public/free proxies is they're often times not sorted by level. So unless you want to do that yourself, you could easily end up on a useless Level 3 proxy and bleed your IP right through. There's also no guarantee as to how long they'll last.