I am long term successful user of ATLAS in my own projects. I migrated from bit outdated autotools to CMake in my projects and I would be like to have support for CMake by ATLAS. I already prepared such file that takes necesary data from ATLAS.pc and check presence of few files and then pass results into variables. I believe that you could add more robust checking. Please, add it to the source which should install it into /usr/share/make/Modules.