HP Online help in no help at all

Probably the most frustrating device that I have ever had the displeasure of trying to get to work. All I want to do is to connect my HP Deskjet 3788 WiFi Printer to my existing network. Having printed the configuration page to find the IP Address of the printer the online help page tells me its invalid as well as the Serial number as indicated on the same page. The worst thing as usual is that one can never find a real person to talk to or even an email address to reach out to..........