I don’t think hacking is necessary to find out where an ex boyfriend lives if you have his full name.
You can find the ip address of skype users, but unless they have an open service running and/or isn’t using a firewall (which windows has by default), then it’s going to be difficult doing anything else over the internet. You pretty much have to get physical access to his device to get anywhere, or trick him into downloading a virus of your choosing.
And to answer your question: No, you can’t find the exact location of someone just by having his IP. Only his city, or maybe his neighborhood. If there is, I would be very interested in knowing about it to.