As easy as it is to get syndicated with useful interesting and unique information, it is
much harder to get syndicated with commercial ideas, especially if the site does not
add significant value to a transaction. Often times links associated with commercial
sites are business partnerships.
Many people do well to give information away and then attach a product to their
business model. You probably would have never read this e-book if I did not have
a blog associated with it. On the same note, it would also be significantly easier for
me to build links to SEOBook.com if I did not sell this e-book on it.
Depending on your skills, faults, and business model, sometimes it is best to make
your official voice one site and then sell stuff on another, or add the commercial
elements to the site after it has gained notoriety and trust. Without knowing
you, it is hard to advise you which road to take, but if you build value before trying
to extract profits, you will do better than if you do it the other way around.