If you have a spare copy of XP lying around your best bet is to make one. If you don't I would suggest going to BestBuy or box store and getting one there or maybe ordering a super cheap one from Dell. The one you make will be much better than one you buy, buy only if you have XP lying around. This is because makers like Dell and stuff get XP (usually around $90) for super cheap. So it works out to be about the same if you don't have XP.