The WEB, for starters, has a lot of info to get you started. Find someone who knows how to use a WEB Search Engine and use 'keywords' to look for what you want. Certaintee is one company that comes to mind, but there are a few others. Offer to buy the beer and pizza when you find someone.
Also, there's the Yellow Pages. Look under 'Siding Materials'. Other than doing the actual legwork, it couldn't get any easier.