Here is an interesting link that helps a marketeer see today's view of the path to purchase.
Ok you will need a few days to fully go through this mega list of marketing tools. http://trackmaven.com/blog/2016/06/marketing-tools-list/
In the video below the guys explore a path to buying an apple mac book pro. With a traditional old school look at analytics you can measure the organic traffic through to purchase. However as discussed there was a ton of TOUCHPOINTS that the brand needed to make happen and won on.
We need more sophisticated tools to measure these 'hidden' touchpoints. Its a little bit related to that 'conversation online'.
There are a great many social media tools available for free - here is a list of some of them.