1) SEMrush - I believe that among all the 3rd party software, SEMrush has the largest keyword database. Their search volume data is pretty accurate and aligns with the Google keyword planner. Also, based on the type of content that needs to be produced (i.e. informational, transactional, etc.), one can utilize different filtering options available in it.

Great article again. I was just thinking why can’t I find an article of yours on keyword research and then boom here it is. Thanks again. On another subject are your articles on link building still relevant ?. As I have been guilty of as Brian Deane calls it the publish and pray method. I would really like to know what is method of choice for link building. Thanks again Ian.
As for the history of the company, as I explained, I created Long Tail Pro back in 2011.  At the time, I was creating tons of niche sites and was doing alot of keyword research and content creation.  I was trying to figure out what types of keywords would rank quickly in the search engines, specifically Google, and I was frustrated with the other keyword research tools (in particular Market Samurai) out there.