I am horribly curious to know how have you guys actually got your SEO knowledge.

eBooks/Courses etc?

I actually worked for a very small SEO company (6 employees) for 3 years then, by a stroke of luck (crazy story) joined Google. (I am now working for a private firm).

I got my SEO knowledge mainly reading the Google Webmaster Blog and then I took an offline.

Sahil K