I took quick look at [Domain Private]
, It makes sense to split your existing site into two.
Having already posted the content, you should be able to tell from traffic stats what green living articles perform best. That should guide you into how broad or narrow your niches should be.
Give the public more of what they want. You also have a wealth of other information from your existing green pages. Do any of those pages rank in the top ten at Google, or the top 20 or 30 ?
In SiteInfo in the Master Keyword List, how do your green living pages rank in Alexa ? What is the competition like, are there already many highly ranked Alexa site occupying the results for your chosen keywords ?
Green liviing is a hugely popular topic but I am sure there are sub niches that have not been exploited. It might be as simple as checking different wording for articles you have already written.
The easiest way to test out associate selling is sign up for the Amazon associates program and look for products you have already used. Write a review on Amazon and write a more in depth assessment on your website. Then post the Amazon buy link code on that page. Best to do this on your top ten performing trafficked pages.
A rule of thumb I find I get one order per 100 visitors and the longer the period required to generate 100 visitors the less likely you will get a sale. 100 visitors over 3 days should still be ok, 100 over a month not so much.
Hope this helps!