Really screen your potential dates and take your time. You will usually get several choices of individuals to contact. You can choose to contact them all, contact a few or only one. You should review their profiles to help you decide to contact them or not. Sometimes you'll get personal messages. It just depends on how the service is set up. Many that have been online dating suggest contacting a few matches at the same time. You can e-mail or chat back and forth to get to know them. It will help you ease into dating again and it will help you decide if you want to get to know any of them better. If you have been talking with someone online it is best etiquette to end it online if you are interested in no longer keeping up the relationship. It is better to do it early than linger on and end on a bitter note.
Allow yourself a second chance at finding someone special, but really get to know them. Consider deeply what you want and give them a chance. Still when you know it won't work then move on to someone new. Part of online dating at some point is talking on the phone as well. It is a way to get to know each other a little better and feeling more confident before meeting. Just be careful and sensible about where you arrange the first meeting.