Hello,

I downloaded MySQL as advised, but i have buggar all idea what to do now. Basically what im doing is trying to allow people to register onto my website. I understand i need to use PHP and a database (MySQL), i am currently learning PHP and i have downloaded MySQL.

What do i need to do, for the peoples username etc. to be sent to the database?

If you get me...

This can get quite involved. You downloaded MySQL. Do you have a dedicated server? Or did you download MySQL for your own local computer for testing?

To get usernames into a database, you'll need to first create the database on your hosting server. Then write the php forms pages to capture the usernames and enter them into the database. There are a few steps involved.
A search on google might find some good tutorials on it. To start, you might check out this tutorial: http://www.swish-db.com/tutorials/view.php/tid/601