I know this doesn't come under programming but i need some help with this.
You may be knowing that the windows hosts file is interpreted before the OS accesses the DNS servers for i.p. resolving.
This can be used for redirection without the user's notice.    www.yahoo.com

The above line if placed in the hosts file will redirect Yahoo to Google( Here, Google has a dedicated i.p. so the task is easy.
However if a website is on shared hosting, how do we add such a site to the hosts file. I believe we cannot add a domain name in place of above hence we always need an i.p.

So how can i make Yahoo.com redirect to a site which doesn't have a dedicated i.p., e.g. redirecting Yahoo.com to netbuilders.org??

Any help would be appreciated.

And your legitimate reason for hijacking is what?

99.9% of hosts hijacks are spammers and other low-life - what's your reason?

For a College Project that i'm working on.
Since the college site is on shared hosting, instead of giving a 'This site is blocked' message from the college computers whenever some1 tries to access a website that isn't allowed(social networks), we wish to have the college site opened instead.
And i believe, editing the hosts file for this is more reliable and resource saving than having to invest in a software that would do this.