Maximum PC

I am writing a program with Java under Netbeans with Swing that will add Contacts, and Manage information about them, but I am having some problems.

I have a list of Contacts, and I would like for the user to be able to:

1.) Add a new Contact, and have the list update
2.) Select a Contact, and be able to enter information about them

However, I don't know how to edit the list, and how see which item the user has selected within the list.

Any help would be appreciated, thanks!

Here is my program if you need it for more info:

http://pastebin.com/Lz54V5Jk