Let's say I have a document that has many pages and some pages have different formats. For example, most of the pages are fine with \documentclass{article} but there may be pages in the middle that I want to be \documentclass{letter}. I want my letter pages to be numbered inline with the other pages and have them show up in the Table of Contents.
Is it possible to change the class used for an individual or range of pages while still keeping things like page numbering consistent across them?
EDIT I'm trying to create a "welcome to the company" sort of document that has a cover page, table of contents, welcome letter, then various sections of information. I've never tried this in anything other than a word processor where it's easy to set "master pages" or "template pages" for individual pages in the document. So I could use a letterhead template page for the welcome letter part and a standard article-type template for the rest and still have the letter numbered/referenced in the ToC.
So the idea was to take advantage of the classes written, if possible, rather than have to format a single page by hand differently from the rest.
Entire document

pdfpages. These can have the same header and footer as your main document etc. – Alan Munn Jan 08 '13 at 00:40\setcounter{page}{2}at the begin of thearticle, and then glue the pdfs of the letter and the article together viapdftoolkit,pdfjam, or some similar tool. The idea of @AlanMunn would also work here. – mafp Jan 08 '13 at 00:51