For partially historic and partially current reasons, detailed satellite catalogs are considered militarily sensitive to some degree... not to a huge extent, but to such an extent that it's prevented the formation of an open, international coordinating system for satellites, keeping most of the coordination work done behind closed doors. The closest thing to an "official" international satellite catalog would probably be that maintained by USSTRATCOM but it's post-facto. UN Space Affairs facilitates coordination and has a catalog but it does not pretend to be complete and has only limited information.

A good source of downlink information is the FCC International Bureau records of satellite ground stations in the US.