I am putting up a web site to sell household products and was wondering how valid the agreements are with people who click a "purchase" button or any other "I agree" buttons that I may have on my site. It's important and I realize it now because I just had a problem I posted elsewhere with a former friend who says since the agreement wasn't in writing it isn't valid. I want to know if these agreements with a click button are and if they are as good as a written one. Thanks.