jepri got it. However, WebDAV may be more appropriate for users who are in your company/organization and are more technical. You may want/need a different system for a more disperse / less technically able group of users.

Look into CGI.pm for all your CGI needs. It's really, really worth learning and a huge timesaver! "Roll your own" form parsing is doomed to failure.

If you're going to be supporting a lot of users, and/or a lot of concurrent users, you should probably look into a database solution. Flat text will leave you flat (ouch.)

DBI programming is pretty simple, if you're already familiar with SQL and database concepts.

You'll also need to think about a couple things:

1. User authentication / session management. There's a relatively good thread here.
2. HTML output. Though this may seem maybe a little ahead of where you're at, I highly suggest you learn HTML::Template, a good quick primer is here, thanks to Ovid. This will allow you to separate your code from your HTML, greatly simplifing maintenance and customizability down the road.