Can the Buddhism.SE site function as "the Sangha" for me? I don't have access to a Sangha just now, and I do frequent this very well conceived and helpful site. Recently I was writing a comment about no longer being a programmer because it was too isolating for my nature ("square girlfriend" = computer screen, ha ha) and I thought: gee, I am staring at a screen now... and for many hours today...

But it is vastly different to be reading and writing with other people (ahem) than to just do an induhvidual activity like programming. Right? I am actually interacting, but somewhat ansynchronously. So I still use and develop some of my Hetaira Archetype skills (more effortful and challenging with only text to interpret and reply by). 

Does asking and answering Questions here count as taking refuge in (and providing) The Sangha?
Sangha means different things to different people. 

Some people who "take refuge in the sangha" are referring to all the enlightened beings who have ever lived and their refuge is in being inspired by the example of such beings.

Some are referring to the community of ordained monks and nuns and they look to the monastic community for teachings of the dhamma and guidance in their practice.

Some are referring to all followers of the Buddha's teachings not only the enlightened and ordained ones. It's more of a "fellow travelers along the path" concept. 

From Wikipedia, "Some scholars have noted that sangha is frequently (and according to them, mistakenly) used in the West to refer to any sort of Buddhist community." The point being there is not one particular thing that is understood to be the sangha that one takes refuge in.

To really answer your question, we'd have to know what you mean by a sangha. But from the context of your question, I'm guessing you mean a community revolving around Buddhism where you can learn and interact with others.

Here is what I'd like to think we're practicing here on Buddhism.SE. It's from the Maha-parinibbana Sutta: Last Days of the Buddha:


  
  "Then, Ananda, I answered Mara, the Evil One, saying: 'I shall not come to my final passing away, Evil One, until my bhikkhus and bhikkhunis, laymen and laywomen, have come to be true disciples — wise, well disciplined, apt and learned, preservers of the Dhamma, living according to the Dhamma, abiding by appropriate conduct and, having learned the Master's word, are able to expound it, preach it, proclaim it, establish it, reveal it, explain it in detail, and make it clear; until, when adverse opinions arise, they shall be able to refute them thoroughly and well, and to preach this convincing and liberating Dhamma.
  


It's a great and wonderful thing that we have a format to try our hand at explaining the dhamma to someone else. It's a great opportunity and a deep responsibility to try our best to get it right. This is a good place. :)

But that said, I don't think it's wise to fully feel that one is taking refuge here as a sangha and depending heavily on it for learning. There are a lot of potential drawbacks. It's very democratic and that can sometimes result in unsound answers getting voted up. We welcome all traditions but that can result in such a mixture of views being expressed it can be confusing to newcomers to Buddhism. This answer to a question about the benefits of sticking to one tradition is a good explanation for what I'm getting at. 

As great as the site is, it's not a solid substitute for learning from a teacher or at a center or in some manner of a structured program. It's not the same as walking into a physical location and feeling the quiet, calm, and peace of a space that is dedicated to meditation; even if you have to travel some distance for that experience occasionally. It's a great complimentary practice, but structured learning and meditation (whether local or online) in a particular tradition may offer the depth of the teachings and support for your particular practice that can't be offered in a short answer, democratic, Q &amp; A format community.