As you already have a database for your forum ( im assuming so anyway ), then just make another table and put them into that.
Then you can just do a select statement like this:
PHP Code:
$r = mysql_query( "SELECT * FROM van_images ORDER BY RAND() LIMIT 8" );
while( $rw = mysql_fetch_assoc( $r ) ){
echo "<img src=\"" . $rw['image_source'] . "\" />";
}
Considering you have a database already, and you say new images might be added, thats probably the way i would do it
---
Otherwise you could put each image into an array: eg,
PHP Code:
$vans = array ( 'van.jpg', 'van2.jpg', 'van3.jpg' );
$vans = shuffle( $vans );
for( $i = 0; $i < 9; $i++ ){
echo "<img src=\"" . $vans[$i] . "\" />";
}