I'm using Gumtree for payment and distribution, it's worked very well for me.
As for marketing, I've just replied earlier in the thread with a little more detail.
For a site with tutorials on game development, most of your readers will be using adblocking software. Therefore most popular monetization methods are: selling a book, a course or locking off content behind a paywall.
Here's an example of premium content:
http://aigamedev.com/premium/interview/dying-light/
Here's an example where the author sells the source code for his articles
http://www.wildbunny.co.uk/blog/
This blog is about all sorts of tech stuff but he sells his book "Game Programming Patterns" (which is very good!) in the side bar.
http://journal.stuffwithstuff.com/