Where to buy IELTS preparation material (books and cds)

hi...i am planning to take ielts test in April. can anyone tell me where to buy ielts preparation material (books and cds) set in rawalpindi/islamabad? i know that we can order official material from British council.but i think it is time consuming and also costly as if i could find the same material in RWP/ISB markets. Also please share your experiences about taking IELTS. thanks