Sure there is, and you've already found it WHT essentially covers almost every aspect of the web hosting industry that you could imagine. Your best bet, rather than buying a book / tutorial, especially with something as fast paced as hosting, just start using the search tool, read up on different aspects of the "biz" and formulate against that, preparing for all things that will arise, and plans in which to overcome those issues.
Please remember, each aspect of hosting differs greatly, so keep that in mind when formulating your ideas.
Originally posted by johnnyb3 Is there any website where I can purchase one?
You may not realise it now, but that's the wrong mindset to have when it comes to a business plan. Only you will know what is right for your business after you have done plenty of research and though things through. As for the business plan, check out http://www.sba.gov/starting_business...ing/basic.html
for the basics of writing a business plan.
A Collection of Web Hosts
Small biographies on hosts, uptime reports and some reviews
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Don't laugh but the Small Businesses for Dummies book has quite a bit of info in it. If you're at the point of "what goes into a business plan" and don't know where to start, I'd seriously say get this. It has a few samples and is enough to really get the ball rolling.