Frequent Flier Blues

ok, i know it's totally lame, but I'm desperately trying to hit 100 000 miles on american airlines this year to get back my executive platinum status. Don't know if i'll actually make it, but it will be fun trying. Tomorrow off to LA, DFW, Cancun... for 4 days. Next month it's Costa Rica for another long weekend. To hit "the number" I'll probably have to hit europe, and probably two trips to the east coast. All before 12/31. Hmmm. Question is what kind of fares can I find for these trips, as even spending $1500 or so would be well worth it for the bennies you get.