There has been much discussion in the past, but as new users of WordPress enter the fold, it's always a good reminder to direct users towards the search feature. While not meeting everyone's mark in functionality, many times it will at least give you a better way to phrase a question, or a general area to direct the question towards. Also, become friends with the Codex There is much information to sort through, from beginner to very advanced users.
When you do need to post a question in the forums, make sure you choose the appropriate forum.
Most forums are self explanatory, but do know that if you are showing of your new design, but not releasing it, it should be in the "your WordPress". If you are having a problem with the design aspects of your site, or a particular template tag, the then Themes and Templates would be the appropriate forum. Also know that miscellaneous is just that, but it's not an off-topic forum as in some public forums, this is purely a volunteer run support forum. If you've got a soap box you need to stand up on, that's what your blog is for. We'll help you build the soapbox, we just don't gather 'round it. :)
And finally, there's a box beside the Topic title "This is a support question". This is important to the many that volunteer on a regular basis. If your question is answered, or you figure it out with some of the resources offered up, mark your thread resolved, and provide the solution if it wasn't answered directly in the thread. Chances are, if you asked it, at least one other person will come along with the same question. Nothing is more frustrating than reading through a thread, seeing your problem, and the person ends the thread with "never mind, resolved", or worse, never returns. They are left to go through the whole process again.
And use the tags feature when you post. A couple of clearly defined words to further classify your post. Even if at first you don't know what to add, as the topic is narrowed, add them. Anyone for that matter can add tags. Ultimately, this feature will equally help future users and questions.
The final, final thing I offer, is to remember this is an entirely volunteer effort. As your knowledge and comfort level grow, don't hesitate to answer a question if you know it, or volunteer in the codex. The more the community grows, so does the opportunity for our voices to be heard in the world via WordPress.