Here in California, you can check online to see if the contractor's license is active, if they are bonded, and if they have worker's comp.

I haven't heard that, and couldn't immediately find it online, but it's possible.

Is waiting until I have finished creating my on-line presence (website and FB) the wrong way to go before I start marketing to motivated sellers and absentee owners.

@Jessica Russell BP is the best place I have found online.

I've wasted precious money on RE seminars, boot camps, online courses etc.

I can't say I have seen a single person go directly into wholesaling full time, it is usually a transition that occurs after they have some experience and have fine turned their systems and built a solid reputation among local investors.

Is it possible to do an online search for tax liens?

Do you have any teachings online, literature or training sites?

This is the best place online to learn about real estate.

I looked online at neighborhoodscout.com and was able to find the residential vacancy rate but couldn't find anything on commercial properties in the area.