You do not pay!! There are some "advice" websites that charge for "guidance" but they are not affiliated to the US Government or Homeland Security. I suggest you were using the wrong one! The website address Wilba has given is correct and the process takes only a few minutes and is straightforward.
Hi! There's a couple of sites offering ESTA. One in particular charges. This is a free one & worked first time for us........Wilba
Wilba, how long does it take to receive confirmation that the Esta has been completed successfully? And do you print something out to take with your passport, to show you have an Esta? I am going to use the site you recommend.