shops are notorious for fucking things up. that said, i would start with the basics. check/adjust tire pressure, pull off all the wheels and retorque the lugs. and just give everything a look over (tires, wheels, brakes, suspension bits) to make sure nothing is obviously wrong. after all that is done, if you're still getting the 'du du du', take it back to the shop and tell them that once again, they fucked up, and to fix it.

btw, are you getting the noise only at certain speeds, or constantly? does it get louder with speed? does it change depending on steer direction? let me know.