Ok well falcon 4.0 headquarters does have the 1.08 patch
From that geocities site, only mirror c seems to be working for the sp4.2 download
This site also has them all other then the one not to be named
http://www.fourthhorseman.net/paveway/falcon.html and the links i tried did bring up the download box, though it does not have the sp4.2 one click installer (it does have 4.0 and the 4.2 patch however).
As for why this stuff is so hard to find, well it directly has to do with F4AF, and them leasing (pretty sure they dont own) the rights to falcon 4.0 and trying to put a stop to all the ""Illegal"" modifications to the original which competes with their product. However technicaly the mods that came before allied force are quasi legal (like any mod), its the one that came out after (that unnameable one here) that they realy activly tried to squash.
As for F4AF, well they are currently at patch 13 (1.0.13) which is supposedly the last patch they are going to make, 12 was suppost to be the last, and i think the one before it as well
. Not sure though what bugs and issues are still outstanding however. This patch was infact released just yesterday.