Try:

SERP Rank

OR

Fast SERP

Sign up to Google Webmasters and submit your site there.
Within a couple of days you will start to recieve data on 'Your top search queries' which will tell you exactly where abouts you rank.
Although it can be out of date sometimes and tell you that your ranking in position 6 when your are not even on the front page!
But still its a base point