I know this has been covered before but I'm not sure where to find it. What kind of anti freeze do I replace the Dex Cool With?

Some use the Dex-compatible/Dex alternative by Prestone, but many, including myself successfully use the "mixes with anything" blends readily available out there in any auto parts store.

If you're brand conscious, then go with your favorite trusted brand, if not then I believe that any of them work as well, as long as you maintain and check your coolant on a regular basis.