Thanks for reaching out to us in the land of the forums. We do apologize that you are not able to connect to the network. We know that this can be quite frustrating. You mentioned that you have just purchased the 80$ Slingbox networking adaptor, which we are assuming you mean the Slinglinks.
We do have one step, that we would recommend that you try. This step is to actually hard wire the Slingbox to your Router, reset your device and then actually start fresh and go through the process again by going to setup.slingbox.com.
Hope this helps,
The Slingbox Moderation Team