I’m looking for the SRPM files used to create the RPM files hosted on the LO website. Where are they?
The vanilla RPMs are created during a build using epm - there is no spec file.
In simple terms the build process creates an intermediate filelist and an tree of files. That intermediate process is processed by epm to generate specific files for rpm and deb that are fed into those tools.
rpmbuild/dpkg is only used to package the binaries that are created during the build, but they are not used to control the build itself.
If they were, one would need to run the build twice. One time for the debs, one time for rpms, and this would be a waste. Building and packaging is decoupled.
So if you want to build your own rpms from the vanilla sources, run
./autogen.sh --enable-epmmake
If you want packages as they are created by $distro, use the distro’s sourcepackage, as in the other answer that points to the fedora srpm as an example.