The Power Supply from ebay is at no use without the split power adapter. You would need to buy this http://r.ebay.com/TOTekO. I myself have one of these http://r.ebay.com/20fvQt. I think its easier you have the power in one safe place, not dangling around. Each camera will be dedicated and if circuit goes it will only blow one, you can identify quickly.
Hope this helps.