yeah that's a start by balancing you're tires. also have them check for tire separation.this is caused when the tire core or belts come apart and the air in the tire inflates the weak spot and causes a bubble on the tire. also make sure that there isn't any suspension problems as well.
after reading this post, I took a trip of about 60 mi. and noticed my vehicle vibrating when I got close to 60mph, so the next day I balanced my tires, took it on a road test into the next town (about 8 mi. away) hit 75mph as smooth at silk.