Originally Posted by
norf9
I always like to use this:
http://matrix.itasoftware.com/ You can't buy tickets on it, but it's a good search engine that lets you scan a large number of cities at once.
While I really like this as well, there are some limitations, namely that you have to limit your searches to a given region.
One thing worth trying is looking at trips to AA's competitors' major hubs, particularly if flying AA requires one more connection than the competition. Also, the more options to any given destination and the higher the percentage of leisure travelers the more likely you are to find good fares. There is a reason why sub-$1,200 r/t fares booking into A/D class can be had on LAX-MIA-Caribbean (in three-class F if you're lucky) while LAX-MIA alone is around $4-5k.