My favorite machining website is Hobby Machinist. I have been a member for a while and really like it. The members are very kind and respectful of one another and that is part of the code of conduct. It is very easy to get knowledgeable answers and there is a section for beginners. Subject matter discussed is categorized making it easier to zero in on the area you want. There seems to be a moderator involved in the discussion quite often. This is definitely top shelf. Very organized and also has a premium content for a membership fee. Yahoo groups activity levels eb and flow and sometimes no activity at all for months.
Dick
OldToolmaker