Wish to experiment with touchpads

I have a few ideas for PC games controllers, the implementation of which require a multi touch pad.

I need a hardware device that will allow me to write drivers for it on the windows platform.

It must be the size of a large man's hand-span.

The device must be very low latency. 

I don't know where to start to look for such an item. Please help.

PS first post on the site. Thank you Tek Syndicate for the sanity of the webpage. I can get where I want to go with a minimum effort, and the ads are not a blight.