I have two Kindle Keyboards (K3) and a Touch, and I don't think the Touch is greenish in comparison. I think the Touch has the same screen as the K3, it's just that there is a lot of variability in the screens. I returned (exchanged) a K3 once because the text wasn't as dark as on my other K3.
With regards to where to get a non-SO wifi-only, with a warranty - I think your only option is Amazon's refurbs. Here's a link:
http://www.amazon.com/gp/search/ref=sr_nr_p_4_0?me=A2L77EE7U53NWQ&rh=n%3A1267877011%2Cn%3A1267879011%2Cn%3A1293320011%2Cp_4%3AAmazon&bbn=1293320011&ie=UTF8&qid=1324396031From what I'm seeing available right now (it does change from day to day), you could get the wi-fi only ($90) and then pay the fee to remove the special offers (30 or $40, I think), or what is more logical given the choices I see today, buy the 3G version that they are offering that does NOT have the special offers ($130). You'd basically be getting the 3G for free in this situation (comparing these two options).
You're right, they won't come with the AC plug, but if you have a USB to AC adapter for anything else, it will work. Or you could buy a generic USB to AC for just a few dollars. I think the refurbs tend to look like-new, and they have the full 1-year warranty.