My friend was recently layed off and lost his H1B status. To remain in status, he applied for H4 based on his wife's H1B. He prepared and filed his H4 application just by following the instructions in the form. He did call the attorney who had prepared his H1B filing but she just reassured him that it's a simple application. So I don't think that the attorney would be of much advantage for H4. If you still want to talk to a lawyer, I can recommend what I'm using for my immigration matters - the legal plan at bestimmigrationlawyers.com. The consultations are unlimited and you will not "break the bank" for such an easy application.