It is frequently in one of two places at my grocery store:
1. With the pre-packaged cheese (not the gourmet cheese - our store keeps that in a separate place), but near the Kraft type cheeses.
2. Often, there is some hanging out in the chip aisle with the salsa and tortilla chips. Perhaps frighteningly, I think Velveeta does not need to be refrigerated prior to opening, so it may be in an area like that.
Oh, I thought of one more. Sometimes it is not in the refrigerated area of the processed cheeses, but on its own special shelf, in that general region...