I understand that you are having some issues in order to locate your Slingbox on your network.
If you are not able to locate the Slingbox, this is the first issue to take care of, otherwise you will not be able to get the Slingbox up and running.
We recommend you to check if the Slingbox shows solid lights. If it is, you'll need to check the security software running on your computer. The following link will provide you with some steps to follow.
Internet security and personal firewalls
Regarding the IP address, this information will be provided by the network router. We recommend you to check the specific make and model for your home router and look up the related information through www.portforward.com