If you want to make direct income from your blog through ads, Google AdSense is something you may want to consider. Google AdSense is a type of advertising program known as CPC (cost per click, also known as pay per click) in which publishers display relevant ads on their websites. It is one of the easiest ways you can make money as a beginner blogger.
PS: my answer to this question is always… “the better question is… how can my blog help me build a profitable business?” Most of the profits from blogging are not made on your blog, but that’s okay. I don’t believe blogging about making money per se, but about branding yourself and positioning yourself within your niche market as an authority and leader. Once that is established, there are so many ways to move people into your money making enterprises. Email marketing, as you pointed out, is one of the best ways to do this. Sending people to your membership sites, services, info products and coaching programs are all great things to route people into as well.
Have in-depth knowledge in your niche? Package it up into an ebook and sell it on your blog. I'd generally advise against selling it (at least exclusively) on Amazon or Kobo, as you'll probably be able to charge much less. If you've already built up a solid audience, you can probably change anywhere from $5 for a very short one, all the way up to $39+.
Once you setup your account on AdSense you will be given a code to add to your blog. This code will automatically display advertisements on your blog from companies who are part of Google’s advertising network. You may see ads from small companies related to your topic, or you may see ads from large companies that are completely unrelated to your topic.