How to get database to populate page template?

Dear Friends,

Jumping into this project with zero experience and after relatively minor boxing matches with the 'Getting Started' guides, I was able to: create a database, build the admin back-end where the db can be edited (ultimately by the client), create the cart and checkout process with pretty good success. Which may make my question sound lame — but here's where I'm stuck —

I have a series of page templates (built in Dreamweaver CS4) with the necessary fields in editable regions, etc. There are 5 product categories, with about 15 items in each category.

How is the dynamic page (that the Web visitor will see) created from these two elements (the database and the template)?

Apologies for the noob question, but I'm at a loss on how to proceed. Any help or direction would be most appreciated.

Thanks in advance!

p.s. eCart rocks — just built a small static site for a client that works like a charm, but how to get the page template populated from the database is throwing me for a loop. Thanks again!