Aside from the other excellent advice, you might want to take a quick look at the program
pl2pm that comes with Perl. Admittedly this only takes your perl library file, gives it a package declaration and adds the Exporter stuff and then saves it as a .pm file with the first letter capitalised - but then again if you have only a simple library that might be all that you need to do :-) Of course this isn't a substitute to reading the documentation that you have been pointed at.
/J\