<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by gleff:
Mike Hoeffner is working on just such a tool. Or you could join AwardPlanner and they'll do the legwork for you.
Alas most airlines don't publish availability for award booking classes. 
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I loved AwardPlanner when I was a member. But they raised the rates over 100%(!) on me, so I didn't re-up.
If my trip were more complicated, I'd probably use their single-trip service. They did a great job with a couple of past international trips that involved overlapping awards, multiple hotel awards, layovers, etc.