Tried to make cheese dip?

i bought a little dipper crock pot and was very excited to try cheese dip last night. i bought melting cheese from walmart from the mexican cheese section and threw it in their and waited hours. it melted but it didnt get creamy-it just sort of got hot and melty. i dont know what i did wrong. do i need to throw some milk in their too? also, what can i do with my random block of half melted now refridgerated cheese? i dont really want to use processed and who im making it for doesnt like cream cheese or mayonnaise. is there anyway to salvage my chunk of cheese preferably for cheese dip?