asda dvds are well cheap....
http://direct.asda.com/Maxell-DVD-R---50-Carry-Pack/000590133,default,pd.html?cm_mmc=gb-_-merch-_-40611
cant find link for plasticcovers but they are like £2 for 50
waheguru ji
this is the asda own brand link
http://direct.asda.com/Asda-DVD-R---50-Pack/000586920,default,pd.html?cm_mmc=gb-_-merch-_-40703-_-Asda%20DVD%2BR%2050Pk