You should probably go after this through a process of elimination

If it only happens on accelleration ayou can eliminate the brakes.
Now your left with the drive train.
Start up the car, put it in gear and attempt to move ahead 'with your foot on the break' Apply lots of power and enough break power that your barely moving.
I'd also strongly suggest you dont try this in your driveway. (just in case)
If there is an engine problem (eg spark miss) it should start to do it now and you can probably fix things up with a tune up

If all is well here I'd suggest that you take the car to a shop where they can run it with all four weels off the ground and have a look under the car at the same time to check out things like the drive shaft, transmission and rear end (looking and listening for the viberation)

Hope this helps
Barrie.