Auto Look up in Drupal Database

This is a re-post of an expired project. I got sidetracked by a new baby, but am back on track now. I have a database of 15,000 funeral homes. I would like to create a field or combination of fields which allows a user to select the funeral home they are searching without having to hit a submit button, i.e. either the user selects a state, then city, then the list of funeral homes narrows to only those in that city. Another alternative is that a user would begin to type the name of the funeral home and a list of relevant funeral homes would appear from the database. In either case, more than just the name would be necessary as many funeral homes have the same name; it would probably have to be a combination of the name and address in order to make the selection. The database is continually updated and this functionality would need to access the data directly in order to ensure that the most complete information is there. The website is built on Drupal 5 with a mySQL database. I've made several attempts using multireference fields and several Drupal modules including the dependent dropdown module. I am looking for someone who can write the code or module and/or provide specific instructions on how I might be able to do this. I don't believe that this project should cost more than $100. Please specify any Drupal experience in your response.