You're right, you shouldn't be having those problems. Is it just a fan you are looking for, or the heatsink as well? I'm using a Tai-Sol forged 742092 heatsink/fan unit, and it's quiet, not too expensive, and keeps my CPU running at no hotter than 125 degrees F when I'm really pushing it. My idle temps are about 100 degrees F or so. Here's a link to a place that sells them. They seem to sell like hotcakes and you'll have to pre-order if you want to get one from this place, but I was glad that I did business with them. My case and cooling setup isn't the best it could be either, but with this heatsink, I'm happy.
Plus, (and this is a big plus), the Tai-Sol has probably the best retaining Socket A clip that I've seen. You can see for yourself. I'm not sure what mobo you are running your T-bird on, but you'll want to make sure you have enough room for this heatsink because it is a big un'..
http://www.inflowdirect.com/
good luck.. Phil