Does anyone know of a website that allows you to search results over user-designed periods? As for example - if I wanted to know who were the best MLB hitters from last year's all-star break to today, over the two half-seasons?

As near as I can tell, fangraphs and baseballreference only permit searches over full seasons.

The question that made me look for such a site was how EE's last 162 games would rank relative to other big league hitters. With a .291/.382/.504/.887 line in the second half of 2011 and a .283/.340/.614/.953 so far this year (excluding today's game) I suspect that he is in Curtis Granderson territory