Im trying to make it so that when people log-in to my site they can go to a certain poage, click on a button (like html button), and an email woill be sent to me saying " So and so bought this" doesanyone know how I could do this?

well if they log in, then you have to have their name stored somewhere. If you alloud ot use mailto in your host, you can look into that, ir if you are like me who run his own server and cant seem to get mailto working, you can do this. Make a guestbook that only you have access to the posts.