I've an idea of Twitter like website which I am implementing on my own. I'm new to web development so I don't know much about the available tools which can make the work faster. I tried many free twitter clones like status.net but so many changes had to be done in their scripts that I got back to coding the back-end on my own from scratch (using PHP). But are their better ways than coding (the back-end) from scratch?
You can try Elgg. It has a micro blogging plugin, user profile system and all the basic requirements for social networking. You can see an elgg demo of the default micro blogging plugin here
Drupal also is a good solution. But you have to customize it for the same result offered by Elgg out of box.