I'm looking for case studies that would demonstrate the ability of
small business owners to utilize the Internet (both website and
e-mail) to generate offline (not e-commerce).  For instance:

-The case study on Company X shows that since the launch of their
website, sales have increased 42%, 28% of which can be directly
attributable to new customers finding the business through the
company's website.

*or*

-The case study on Company Y indicated that the company has noticed a
39 percent increase in repeat buying after the company instituted an
e-mail system that would send an automated thank you to customers who
left their e-mail addresses while making a purchase.

Something along those lines.  

I'm looking for at least 3-5 case studies, the more detailed the
better.  I'm trying to build a case for why small businesses need
websites.  It's intuitive for me but I'm looking for some factual data
(both empirical and anecdotal) to back up my theory.  To that extent,
please feel free to let me know of any other information that you
think is relevant.

Thanks!