@Karam I think you're wrong...

1) It can. But the IP must be a website. So for instance, mutualised-hosted site won't work.
In layman's term : you can redirect to Google.com, but not to comax.fr...

2) just redirect to 127.0.0.1 to block a website (any IP would do of course as long as there is no server running on port 80...) but this is the way it's mostly done.
About metasploit, yes but I don't think he's here yet...

3) Wut ?! Of course you can do it however you are connected... ARP is independant from the type of packets used. It's *Adress Resolution* Protocol so... It resolves adresses whatever the source.
Now, if you are saying this in regard to the use of the cell phone, you might be right since I don't have the phone and don't know how it works when plugged.
If you were talking in general terms, then I suggest you read OSI model to have a better understanding of how the network works : http://en.wikipedia.org/wiki/OSI_model