Mika - accommodation anywhere near the event will most likely be fully booked by now: it is for months before the festival, sadly. I'd recommend hiring a car for your stay, and staying somewherenice in the country an hour's drive away, and driving in. The Suuth coast is a good bet for somewhere picturesque to stay and then drive to Goodwood. See if you can find something on the other side of Chichester.
The Mr & Mrs Smith website is a favourite of mine good for decent hotels.
http://www.mrandmrssmith.comGood luck!
Harry.
