Big problem in our new (to us) house! It was awful. We used every kind of trapy.... glue, snap, poison, the kind the shock them to death... others too.
Finally, we got two of these:
http://www.amazon.com/Sharper-Ultrasonic-Rodent-Deterrent-SI310TNM/dp/B000A3I9QY
And have never had a mouse since. They put out a sound that the mice do not like. Of course humans don't hear it! Best 100 dollars I ever spent!