I use a product called
"Blist-O-Ban", though I order them from Amazon.com not this site I linked to. I sometimes get one on the side of the ball of my right foot. Don't get them anywhere else, though.
Did you get your stride tested before you bought your shoes? It could be that they are designed for a different footfall than what you have and that they are rubbing the wrong places?
Also, what kind of socks do you wear? I did get serious blisters when I wore looser cotton socks. I bought special running socks that were for my shoe size, got them from Road Runner Sports.com. They are moisture wicking, mild compression socks I think. I forget the fabric. They are great - they don't slide, don't hold moisture, don't bunch up, support my feet. Love them.