A very advanced solution for a high volume of job files is CNI's AdDesk.
I say "advanced" becuase it goes beyond a simple fill out form (which some clients ignore, or fill out incorrectly).
AdDesk uses a web server to Serve-up XML coded pages tied to an SQL database, which in turn, informs the production and billing systems. Client then can access digital proofs, and communicate edits. via the web interface.
I'm guessing this is likely above your needs or budget. But I like to highlight "large enterprise" solutions, in order to glean principles, that may adapt to a smaller scale.
In a smaller scale, you will need at least , an internet service software (Apache, IIS, Tomcat or the like) providing a web page. This web page could have simple information and a PDF form to download, fill-out, and upload back to your shop (Some instuctions on PDF form usage would be needed -- that's why the web page). The web page can link to your FTP server.
This might be a good transtion point into JDF for your shop as well.
Info on JDF >
http://www.cip4.org/
Then this PDF form can acompany the print Job PDF for production management.