What site should I use to jailbreak my iPhone 4 iOS 6.1.3?

I looked some up and found icy snow but I worry it might be fake. There's also snoebreeze and a few others, which I'm not sure if they are untethered. Has anyone managed to jailbreak their iPhone 4?

Let me make this perfectly clear. There's NO untethered jailbreak for iOS 6.1.3. Every site that tells you that they can is a scam. They will either charge you money and you'll get nothing in return, or they will claim it's free, but you'll download adware.

The way they work is - you pay them for the jailbreak software. They give you the one that you can get for free. When you complain you can't jailbreak your current one, they'll just wait until the newest FREE software is released and give it to you. Not only are they selling a product that is not theirs, they are selling a product that is FREE!

Some are getting more clever and saying you only need to fill out a few surveys to get the software. What happens is, they get paid by the companies that make these surveys and you get the same scenario as above.

Download the latest version of redsnow here: http://www.iphonehacks.com/download-redsn0w.
You'll also have to download the 6.0 ipsw for your phone. As long as you are on an Iphone 4 and not 4s you can have a tethered jailbreak. This means that every time your Iphone reboots, you will have to connect it to the computer and run redsnow again.

This site gives pretty good instructions:
http://www.ujailbreakiphone.com/2013/04/jailbreak-ios-6.1.3-tethered.html