You can use find if you use the -prune and/or -only options for find. I see prune is in the UNIX Nutshell book, but the -only option may not be available in some OSs.
They can help you limit your search parameters and prevent recursive directory searches.
if `find . -name "*.F" -prune -only 2>/dev/null |wc -l` -eq 0
This will only search the current direcory and give your comparison.
