One thing to keep in mind - databases are used for a reason.
Flat files are very limited and can get corrupted. Databases are easy to backup and are very scalable. Most hosts include PHP and mySQL for free. DW makes it very easy to connect to a database. Once you learn a few simple procedures, you have a whole new world at your disposal.
Maybe a few tutorials will make it easier to see how it's done:
How to create a connection to a MySQL database
WA solutions come with the file to create the database so all you need to do is follow the import step of this article:
Exporting and Importing a database using phpMyAdmin