Re: I want to point my pre-existing GoDaddy domain to my BC site, but I just don't know what to put in the GoDaddy DNS Manager.

If you have already added the domain to your site then please point the domain to BC name servers ;

ns1.worldsecuresystems.com

ns2.worldsecuresystems.com

ns3.worldsecuresystems.com

This document include the steps :

http://helpx.adobe.com/business-catalyst/using/change-site-domain.html

Thanks,

Sanjit