I use ice cups sometimes. It doesn't get a very big area but is good for pin pointing an area. In the winter (northwest) I'll go to an outdoor pool that isn't heated. It is usually right around 55-60 in the winter.

Use the ammount of ice that can fill asmall garbage can... at home ice baths can be way too cold because you dont have a thermometer. Just use less ice then you think you need, but Matt is right... Ice cups are awesome!!!! But, You gotta know that ice baths arent meant to be comfy!