You opened your own datacenter and don't know where to get equipment from???
To be honest what customer would goto a datacentre using old equipment. If you want to beat your competitors like choopa etc, you need to buy new equipment preferably top of the range.
Reccommended choice for switches for example would be a Foundry BigIron and obviously ciscos for layer 3.
Don't use eBay. Take this from soneone that knows what they're talking about. You see people here telling you to use eBay that has never even owned or operated a data center.
If you want a reliable data center DON'T BUY FROM EBAY. Buy the equipment new or recerifted from a disturbor. Come on guys don't be telling him shit unless you're operating a data center or own one.
Hostaffect is right eBay is ok if it is just junk you want or that new semi stolen mobile phone but for a data centre you need equipment that if it goes wrong with in the first 12 months you can get a replacement or repaires.
I would Recomend looking on a search engine for your country and look for a decent dealer or for a company that ships to your country.