The Grishneshwar Jyotirlinga is situated about 30 km from Aurangabad, making for a 40 minute long drive.
State run buses operate regularly between Aurangabad and Ilapur, the place where this shrine is located. You should be able to find out more at a local bus terminus.
For your reference, here is a route map from Aurangabad to Grishneshwar Temple:
Hope this helps!