Somehow, Facebook has decided to join my mail program! I might have inadvertently invited them,but have no idea how. They are in my contact list and don't want them there! Also, my mail is only picking up a few of my contact's addresses when I try to write or forward an e-mail. Can someone please help me?

For the second part, try a restart.

Hold down the power button until the power off slider appears. Slide it off. When the iPad finishes shutting down, hold down the power button again until the Apple logo appears.

Also, go though the Contacts app and make sure those contacts really are still there.

For the first, there isn't any way for Mail or Contacts to add you Facebook addresses directly. Things you should check.

Any Facebook app you recently added. Go though it's settings and make sure it doesn't say something like importing Facebook contacts.

Your mail account on the server. Go to the web site and make sure you haven't done anything to associate your account with FaceBook.

If you have another phone or device that is syncing with the same account(s), make sure it has not associated itself with Facebook and syncing those contacts. This is a common default for Android Facebook apps.