Jhav wrote...
You might find this useful: http://animecons.com/events/
I don't think there is anything MASSIVE happening during that time frame unless you want to count the New York Comic-con as an anime convention - I wouldn't. However, there are a bunch of smaller conventions happening all the time around the nation. Hopefully you'll find one near wherever it is you are staying.
Well, NYC Comic-con now includes what used to be NY Anime Fest. You just get admission to both.