The best places are our forums ( http://productforums.google.com/forum/m/#!forum/webmasters ) and our regular webmaster office hours ( http://sites.google.com/site/webmasterhelpforum/en/office-ho... ) where a webmaster support Googler (me and a few others) have a hangout on Google+ that anyone can join and ask about their site. We do them in many languages and time zones to cover the world as much as possible.

Obviously we can't be everywhere and we can't answer every question, but we try as much as possible to help when we can.