Display results from Plugin

[Jaiibee]

Ok, so I have made my own plugin called "Custom Classifieds Listing", with a name of "Automated Classifieds Listings"

$sql = mysql_query('SELECT * FROM vb_classifieds_ads WHERE categoryid = 1');

while ($row = mysql_fetch_array($sql))
{
echo $row['title'];
}

That's what I've got. It display the only entry that's in that table, however it displays it at the top of the page before the header.

Ok, so basically, I want to know how to position this output in my templates.
I want to be able to say "$post[ccl_posthing]" and the results from that MySQL query is displayed.

I know this is very basic, and most likely covered where I haven't already looked, but any help would be greatly appreciated.
Thanks.