i have a few account that i want to get rid of but how do you do it???

Your going to have to ask an admin to delete but for now ignore the sites are there.

Perhaps if they decide to change their control panel anytime soon, they could add a button that could delete or send the people who could do this, a message to have it deleted. If they ever do, they should also have a text box to enter ya password for the chance that the button was hit by mistake.

or just had a popup box that asked "are you sure you want to continue" or something

popup boxes wouldn't work. Alot of people just click through those things because they don't want to look at them. Most people don't actually read whats in a popup box. I think the best option would be to have to type your password after you press delete. With some nice LARGE RED FONT saying:
Are you sure you want to continue and delete your account?

ya true. very true. i do that alot