Research has shown that having or not having a search button makes no difference to pro users. However, for novice users, right search buttons are generally slow and inefficient. To me, the solution is simple. A left search button reduces visual fixations, puts the label first and makes doing searches faster for users.
The pattern left search buttons follow is similar to IXDA's search where the combo box and icon come before the text field. The label and button have more visual weight and are what users need to see first before they carry out a search, which is why I believe they should come before the text field. Despite the fact that most websites and search engines have it backwards, what are your professional and experienced independent thoughts on this matter?