Hey bobbyg, not sure whay you can not get in to
www.auto-res.net 
I just went there and had no problem, may be a location problem connecting from Hong Kong. Also, if you are trying the English version, it is still under construction so maybe that is causing the problem.
Anyway, my best info tells me that AutoRes does not go to Chinch�n, nor do any of the other Major bus companies that run out of Madrid. The company that can get you to Chinch�n from Madrid however is called "La Veloz" (tel: (+34) 91 409 76 02) from the Estaci�n Conde de Casal (Metro: Conde de Casal).
They have no website but there are busses to Chinch�n (aside from all day long) in the afternoon/evening leaving Madrid at:
7:00, 7:30, 7:45, 8:00, 8:30, 9:00, 9:45, 10:15 and the last one at 11:15pm.
Saludos,
jer...