B2B Travel Booking System

Need a technical design document for a B2B travel booking web application. The system will handle bookings for: Hotels, Flights, Transfers, Sightseeing tours & Car Rentals. While the data will be supplied by either international suppliers (such as expedia) through XML integration or from local and small-sized suppliers who can fill all this data manually through a form-based pages. Tour agencies will be registered to the system in order to search & fill their booking orders. Monitoring the financial invoicing and credit-limits for each agency will be a given. I'm expecting to have a clear structure for all the modules, services, screens and object module diagrams for this application.