Your starting to get the idea. The job of normal mapping is to transfer the information from the high rez object onto the low rez object. Here is a "how to" of the process, but first you need load the plugin from your settings and prefferences. Look for a plugin called transfer surface info and check it. By the way Normal Mapping is a feature available only in Maya 6 or above.

First pic is of a high rez object and low rez object.