about create Makefile

hello!
i want to create a Makefile on the freebsd 4.5,so i vi the hello.c

#include
int main(int argc, char** argv)
{
printf(''Hello, GNU!\n'');
return 0;
}

#autoscan
#cp configure.scan configure.in
#vi configure.in
modify:AC_OUTPUT AC_OUTPUT(Makefile)
#aclocal
#autoconf
#vi Makefile.am

AUTOMAKE_OPTIONS= foreign
bin_PROGRAMS= hello
hello_SOURCES= hello.c

#automake --add-missing
configure.in: 17: No files mentioned in `AC_OUTPUT'

BUT WHY???

thank you very much!!!