Generating Related Drop Down Boxes

Hello all: I have searched the archives, and although I know this is probably there can not find it. I'm probably just not searching for the right subject. Here is what I am looking for. I have a table with Location and Hotel, and another one with Hotel and Accommodations. I need to generate the first drop down box with locations. Then when you select a location it will place the corresponding hotels in another drop down, when you select the hotel it will do the accommodations. What I am looking for is if anyone has a sample or any information how to do the drop downs that update themselves. If I can get a sample for one I'm sure I can figure the rest out. As always, thank you for all your help. Mike Walth CinoFusion