I dont ever recall that being the state of play, People have asked questions about internet security and gathering IPs for security reasons before - and its been responded to. But you've gone from asking about aquiring an IP address, to learning HTML/PHP, then to fake login pages. Why would you want to make a fake login page unless it was for aquiring a Uname & Password of someone which wasnt given with concent? is a violation of this sites AUP (Acceptable Use Policy).
besides even if you were to succeed in aquiring the requested IP address :
Routers thesedays tend to have integrated Firewalls(Firewalls block unauthorized access to your PC) It would be virtually impossible to access someones home PC unless like mike explained earlier:
Secondly, you might end up getting a proxy server and not the users real IP address. Proxy servers are used everywhere thesedays to mask peoples real IP addresses.
Additionally (without getting too *********.) Some users have Dynamically assigned IP addresses. This means if they break the connection to their ISP (restart the router for instance) a replacement IP address is assigned to them.
Sorry if this post seems heavy handed at the start but you've gone from asking people about legitimate security questions (which they've taken the time to answer) to more like a walk-through on hacking and Uname and password harvesting.