Answer 1, Authority 100%
Maskmum What you can find on the Internet is:
1 – lessons and articles How to use this or that technology (Introduction – Continuation – Master Class)
2 – Very generalized and not meaningful articles about GameDev as a whole.
To write a game – you need to think from beginning to end .. ready and there are no more chewed solutions !!
Since today the technology does not stand still, I offer you to try to make your online game, according to HTML5 technology, namely canvas + js. There are already such games http://html5games.com/, and how to create them can be searched in Google. For example, I found a person in a blog: HTML5Development . Also in Habrahabr You can search, there are many interesting articles on this topic.
It seems that this site gamedev.ru specializes in this topic, there is a foreign analogue of GameDev.net.
And there is still roller interesting for use RaphaelJS + box2d.