I needed to talk to the database from an app that builds in Visual Studio 2010 only at the moment. The binary that EnterpriseDB provides for windows was built with VS2005 I think and causes the weird error linking of "cannot open Files.obj" (there is no Files.cpp)
I was able to download the source and get just libpq.lib (and the dll) built and am testing it in my project, it loads and sends queries to DB. I downloaded source and ran the "perl mkvcbuild.pl" I opened solution in VS2008 letting it convert project. I opened in VS2010 and let it convert the VS2008 project. Now I added to the linker properties for the libpq project ws2_32.lib,secur32.lib,wldap32.lib and then the libpq.def file I built just the libpq project and am using the libpq.lib it created. I hope we get the full build later, I really need to remove a lot of cruft for an embedded target.