Mac OS X Manage Login Applications

Log in as the user who wishes to have a login item or as an admin user.
Choose System Preferences from the Apple menu.
Choose Accounts from the View menu.
Click the name of the user.
Mac OS X 10.3.x: Click the Startup Items button.
Mac OS X 10.4 or later: Click the Login Items button.
Click the "Add {+}" button.