Retrieving data out of mailbox

For 2 years, we had a form in our website, in which visitors could put their details. When hitting the send button, it would just send the form data with a php script to our email, which is a gmail account. Now, we regret that decision and want all this data in a database, instead of in our mail box :) So, what we need is a program, that: 1. scans through our gmail box for mails with certain subject 2. open the mails and retrieve data from it 3. stores it in the right column in the database. The database type does not really matter, can be CVS or Excel or MySql. The retrieval tool can be in any language, like C# or whatever. It can be either accessed directly from gmail, or we can try to download the whole mailbox with pop3 and scan it that way.