I have a question regards to ASP.NET 2.0

I'm developing a travel website, using a SQL Server 2000 database. This database contains COMPANIES table, which stores all travel company info.

Now, I would like to store some extra info for some kinds of travel companies (not all companies), for ex only for tour operators, hotels and travel agents.

I intend to design the database like this:

COMPANIES (id, name, ...)
TOUR_OPERATORS (id, company_id, ...)
HOTELS (id, company_id, ...)
TRAVEL_AGENTS (id, company_id, ...)

Each tour operators, hotels and travel agents has all properties from COMPANIES table (company_id is foreign key) and some specific properties.

Now I have to build a listing page, a search page, and a detailed page for all companies.

I would like to know if there is a better solution to design the database and how to build the listing, search and detailed pages. Do I have to build 3 different pages for each type of companies or should I use only 1 page and use "if/else" there?

Thank you very much.