Generating Documents From a Dynamic Site

I just created my first web app and now I'm trying to figure out a way to
export the data from my webapp to printed sheets. Basically the system has to
generate things like packing lists, bills of lading, invoices, etc....

Right now, I create the document in HTML, and popluate it dynamically. I'm
using Print CSS to control the layout...but I have no idea how to handle it if
the document is bigger than the page (ie pagebreaks, page numbering, repeat
header/footer, etc)

Does anyone have any idea what I"m talking about.