I am generally pretty happy with the Alien Bees (2x B800's) on a cost and performance basis. With your budget, I would go with 1 - B800 and 1 - B1600, two of the Alien Bees' carry bags, a couple of Manfrotto stands and umbrellas or soft boxes. That should leave a little extra in the budget to buy some toys to play with.
While your budget is decent, if you want a cheap starter monolight unit, Adorama is offering a 300 ws monolight, the Flashpoint II Model 620, which looks pretty good at $199.00. I haven't tried it, but the specs looked good. I took a look at it in their store last week. It's not configured like the Bees. Its more of a rectangular than square design, like my old Novatrons. At 15" long, it didn't work for my travel needs.
Just my opinion....
One bear's place...