Paypal and htaccess

I am using htaccess to secure a few directories on my site, and Using paypals subscription to creat the login information for each member to verify payment is received.

What I need to do is creat a database for paypal to write into (May have this tonight) and a set of scripts so when the database is updated so is the htpasswd file to grant instant access to the section each member has purchased. so either I script to overwrite the txt file or a way to connect .htaccess to a database if either can be done. Both the database and the password lists will reside above the wwwroot for added security. Any help here is greatly appreciated as I am knew to scripting and this will be my first non ASP/vbScript dB.

Thanks,
Caspur