I've just been told off for asking a question in the wrong section and that I should have asked it in the main section. However, the main section doesn't have an "Ask Question" link that I can find! Stupid question (since I found it in this section), but how do I ask a question on Stack Overflow?
I assume you are talking about this question on Android Enthusiasts: https://android.stackexchange.com/questions/18674/is-there-a-library-that-can-display-font-ligatures-on-android
If so, you were not "told off". You were instructed about where to properly post it.
As for where the ask question link is; it's in pretty much exactly the same place on each site. The page to do so on Stack Overflow is here: https://stackoverflow.com/questions/ask
I think some of the disconnect here might be due to how you perceived there to be 'sections' of a 'main site'. Going on an assumption like that, I can imagine how you would arrive at some of your confusion.
Basically, the Stack Exchange network contains about 80 sites as of right now. It is essentially impossible to have them operate as 'sections' of the same website, as a result. However, I believe a conscious decision was made that it was desirable to split the sites like that anyway, and allow each to operate as a separate community.
Yes; that absolutely does somewhat decrease the usability across the network, as far as navigating between them all. There are elements of the main Stack Exchange site which mitigate those issues for those of us with multiple accounts, though. Also, though; the various communities span a broad range of topics, and it would be even more harmful to usability to force people to have to navigate amongst content that is not at all related to what they are interested in; For example, I have no interest in ever seeing any content from the Gaming or Cooking sites.
There are more reasons why that I could go into, but I'm not even 100% sure I'm right about what the disconnect is. There are questions here that can help you understand why the communities are split like they are. My point is just that it is on purpose that the communities are split.
Stack Exchange is not a forum. You're going to need to approach this network of Q&A sites with new eyes.
When new users struggle with our format, invariably they are accustomed to participating in forum environments, where you can pretty much do anything you want. That's not the case here; we apply a bit of discipline to the proceedings to keep the signal-to-noise ratio high for our participants.
To quote Yoda: "You must unlearn what you have learned."
Everything you need to know about using Stack Exchange sites can be found at each site's FAQ pages. For Stack Overflow, these are: