How do I get valid card numbers? (without having to buy) please help

[Mayson]

If we're talking about collecting fresh CCs in bulk, then your most realistic route is to hack into an ecommerce shop/service and passively collect plain-text CC information through the use of form-grabbing scripts. Alternatively, you could employ email phishing to promote replica landing pages or specialized malwares. There are other methods, of course, but this is just to give you a simple idea of the route you'd need to take.
Good luck.