Not sure what is economical to you but I would recommend
Alien Bees . They are inexpensive and relatively durable from a construction standpoint. They have great customer service, too. Only downside is that the modeling light in them kind of sucks - not enough power but definitely useable. Anyway, you can get a nice set of two strobes and accessories for $600 - $800. For the price, they are hard to beat.
If you have a little more to spend, Elinchrom has a nice set of monolights as a kit that goes for about $1000 at Adorama and B&H. One version of the kit includes a travel case.
Hope this helps,
Herb