I believe most CSers are very helpful if you know how to ask that is...
Sell-fish? That's being too generalised, it is true and you'll have to expect that in ANY world, forum, community, country, office, organisation - that is the real world. But I wouldn't say EVERYONE is... So far, I've received much useful help and advice from CS... some blunt (but hey, I don't expect everyone to be perfect)...
Frankly, when I read your question, I felt that giving you a simple short answer isn't going to be easy because it is really a question with many many compound questions compact into one... Simply put, quite ambiguous... and also it gives you away as someone who need more help with the basics than a simple direct answer... That is why I mentioned you need to know how to ask... No offense intended.
So, do not easily mis-read other's comment as if they are selling-fishies okay? :sweatsm: It is simply that your question demands very complicated answers that one or two paragraphs will not be enough - they got time or not, let alone you may not be able to understand as well??