There's a service on LinkedIn called Answers. Any LinkedIn user may post a question and get answers from other users; everybody's may give his own advice, suggest links or the name of a supposed expert on the topic proposed. What happens, as everywhere there's a free-not-moderated-everybody-get-in access (which is ok), is the signal-to-noise ratio is quite in favour of noise. For the very peculiarities of LinkedIn everybody's looking to stand out of the crowd, or to promote his own business. Which, again, is ok. As long as you have something intelligent, and honest, to say and you're really trying to give out a tip to somebody's that maybe really need some help.

SEARCH ENGINE OPTIMIZATION IS TOO EXPENSIVE for small office & home office’s websites. Any advices?

This is the question asked. A very interesting question, since it touches a common problem to lots of small/on a budget business in a global and more and more competitive digital business world. I don't know why, but SEO looks to me one of those fields where sharks are more common. I'm sure you know what I mean.