It seems that you are having some issues in order to get the connection to your Slingbox using the SlingPlayer for iPad.
The first step is to add the Slingbox information to your Sling Account. Once you add this information, you only need to launch the SlingPlayer for iPad application and then log in to your Sling Account.
This process will allow you to select the Slingbox on the iPad's menu. Right here, you will be able to select the Slingbox, which will be listed under the name you set for it on the Sling Account. Once you tap on it, you will be requested to enter the Slingbox password, which is the same one you use on your computer.
The following links will provide you with further details and information that will help you: