Page size should follow one of two rules.

Most Web Pages should be designed with a dual use; the Internet and normal publicity.

Why have special literature, when you can just print the page off the Net? So you just make most of your pages a single A4 or thereabouts, so that if a customer wants details on one of your products, he or she can print one sheet, that tells him everything.

If they aren't Interneted, you can print the page, and say you're saving paper and only have one set of literature, so that everything is completely up-to-date.

Then there are informational pages like this.

Just let them go on and on, giving all of the information, with lots of links, so that people can jump around the text.

BodgeIt! gives complete control of page size in the Web Site.

It can also generate a second set of Web Pages for use with printing.