Taken from a website (Information might be out of date) :

Street parking or alternatively there are a few private matchday car parks at some local industrial units near the ground, or at Hawthorns station which costs £4. David Dougal a visiting Sunderland fan informs me; 'I parked at the Beeches Road Methodist Church (B70 6QE) at a cost of £5. It is covered by CCTV and is about a ten minute walk away from the Hawthorns. It was easy to get back on the M5 from the car park once the match is over.' Just around the corner from the Vine pub on Roebuck Lane is a St John's Ambulance Depot that offers matchday parking for £3. There is also the option of renting a private driveway near the Hawthorns Stadium via YourParkingSpace.co.uk