I purchased all the dlc back in 2007, and now the downloads are dead. Is there another place to download them or would contacting support be my only other choice?

You could post this in the software issue section. But what do you mean by dead? They are checked in the launcher but still won′t work? If possible you could try a reinstall of everything but I don′t know how it works with downloads.

The downloads are dead, as in the web address given to me via email to download the dlc are 404, not working.

I would be able to find a fix to any problem the dlc would give me if I could just find a way to get the dlc I purchased already.

Send http://www.gamesas.com/user/365941-gstaff a PM stating your problem. If you have proof that you originally purchased them, he'll be the guy to talk to.

Why did you delete the installers? Don't delete such things if you've purchased them.
On the other hand, you could buy the goty deluxe with all the stuff in it.