When I travel, I visit the quilt shops. I usually buy in 3 yard increments. Then I go to the local Fed Ex store and ship all my fabric and notions home, so I don't have to lug the weight around, or pay for extra luggage on the flight home.
If I travel internationally, I stuff my luggage and carry on as much as I can. Don't want the postal service and customs to lose my new stash.