Reddit mentions of Ultimate Guide to Google AdWords: How to Access 100 Million People in 10 Minutes

First:
http://www.amazon.com/Ultimate-Guide-Google-AdWords-Million/dp/1599184419

Second: http://www.amazon.com/Advanced-Google-AdWords-Brad-Geddes/dp/111881956X/ref=pd_sim_14_3?ie=UTF8&dpID=51qNA-w7TXL&dpSrc=sims&preST=_AC_UL160_SR127%2C160_&refRID=067Y1BH3800X4A8QJ62N

Third: Take Over The World.

Not a course but this book by Perry Marshall helped me out a lot when I wanted to learn more: https://www.amazon.com/Ultimate-Guide-Google-AdWords-Million/dp/1599184419

This is a good starting point:

Perry Marshalls: Ultimate Guide to Google AdWords

Hal Varian: Quality Score & the Ad Auction

Take everything you read/learn online with a grain of salt. PPC is not black and white, not every practice works in every industry/budget/account. Try to learn the logic behind making intelligent decisions in PPC.

I would get two books in particular. I actually just read them and I quite like them:

this first and then this one

Perry Marshall might rub people the wrong way with his insanely long form sales copy but he's been an amazing resource for me and my learning. He sells courses online that are worth the 200$ if you're really wanting to study yourself.

In my opinion, start with a joint book that's regularly updated, see if you like Perry's teaching style and then maybe go for a course. His website really is a good lesson in long form sales copy. (Which in his niche works well, especially for people in your mindset)
http://www.amazon.com/gp/aw/d/1599184419/ref=redir_mdp_mobile

Sorry for the mobile link, but Googling or Amazoning Perry Marshall will get you what you're looking for.

If you want to validate this idea, try Google AdWords. If you don't know how to use it well I would highly recommend this book.

Any traffic you're not converting now is kind of meaningless. If you posted the page out on your Facebook for example you might get a few people checking it out but they are not your customers. Maybe they were there to check out the upside down santa girl not your product.

Google AdWords let's you almost instantly turn on / off a stream of qualified leads. People searching for "how to start a pub crawl business" or similar. Get this traffic coming in, see how much you're paying for a conversion (email signups). 30 conversions from AdWords is statistically significant enough to draw conclusions. Then crunch the numbers and see if they make sense. Hopefully this will only cost you about $100-$200, and if it works you have the emails of interested people already.