Need help with MySql queries

[macky]

First, the background, I'm doing an RPG, when you sign up, your class you chose is inserted along with your record, into the database, each class has a number.

What I need is code that would allow me to take that number, write it as a variable, then do a few if statements, to eventually lead up to the displaying of the class as an echo. 

What I don't know how to do, is get the results of a MySQL query to be stored as a variable ($class)

(none the less, how would I search a given table for their username / then find their class)

I'm very new at PHP coding, so the more explanation the better :-)

Thanks in advance, and sorry if its already been posted somewhere.

[hostfreak]

Maybe something like:
[code]
//Url would be something like www.domain.com/index.php?username=USERNAMEHERE
$username = $_GET['username'];
$query = "SELECT class FROM table WHERE username = '$username';
$result = mysql_query($query) OR die(mysql_error());
$row = mysql_fetch_array($result); //www.php.net/mysql_fetch_array
$class = $row['class'];

if ($class) {
//blah blah
}
else {
  //etc etc
}
[/code]