Booking / Availability Calendar for Wordpress

I am looking for a booking resource system to be developed for Wordpress. Basically, I am looking for something very similar to this : [login to view URL] I suggest looking at the multi-site admin/client demo of that website ([login to view URL]) to see the functionality that is offered. I could take the time to describe what I expect from the script, but I am fairly serious when I say : I am looking for precisely what can be found at the above link, with ONE exception : 1) Search feature -- Visitors to the website must be able to 'search' through ALL available calendars for a free date or dates. ----- To accomplish this, the search feature will include a 'blank' calendar. The visitor will click on the date or dates he needs free, as well as checkbox indiciting only search for calendars which match 'all' of these free dates, or 'any' of the free dates ------- The search must be organized by category as well; for example, the person should be able to select 'February 22nd 2011', and also select, 'Canada'. Or 'America'. Or 'Brazil'. And only see results matching that category. Ideally, it will be able to filter these results acording to Wordpress categories. ---- Search results must be returned using the wordpress [login to view URL] page, or a similar page; basiaclly, the results must seemlessly integrate into my wordpress website, and not be a function of the script itself (unless in the script, you simply duplicate the wordpress design I have, which is fine).