If you have that pack you will have a max discharge of 60a and a nominal voltage of 36v. If you are going to get the cells from eBay look on over sites like nkon and lithium ion wholesales as the have cheaper prices
Before assembling a battery with alot of energy you should do research and feel that you know what you are doing. One of these cells has potential to creata a fire. @oyta provided a good link to get going.