Great question but a toughie... without a subscription to Baseball Prospectus, I wasn't able to get any sortable information for 2006 at this URL (which list all position players):
http://www.baseballprospectus.com/statistics/sortable/index.php?cid=9653
The best I was able to turn up was a pre-sorted "best of 2005" list based on the B.Prospectus' metrics - below...
Best of 2005:
http://www.rotoauthority.com/best_of_2005/index.html
Permalink - Best Centerfielders of 2005:
http://www.rotoauthority.com/2005/11/best_of_2005_ce.html
I'm aware that this list is not really all that useful since these ratings can change dramatically from one year to the next.
Maybe the best solution is to contact RotoAuthority and find out when they'll make their 2006 list available. I have a suspicion, though I didn't verify... that perhaps Baseball Prospectus considers the sortable data proprietary. This might explain the lack of sites that are using or posting this information.
Good luck!
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