Menu/form help!!

Hi, I am trying to find a plug in that can pull info from a database.

I have a holiday site and would like to create a price generator that feeds out a price dependent on the date/location/room type/number of people etc. So basically a drop down menu and what the client selects changes the price.

Unfortunately I have no idea what I am looking for..

Any help would be so greatly appreciated. My site is: http://naturistholidays.com

Kind regards

Ed