Do you mean you bought an item that was not sold through eBay?
Without Paypal, an off-eBay purchase becomes much more likely to be fraudulent. The seller found you through eBay, but is cheating the company out of their fees by taking you away from the site.
That may seem fine to you, but what makes you think they will treat you any more fairly.
You can go to your bank and buy a wire transfer. As heidi says, it will cost $25 or more. (These transfers are very cheap and much used in Germany.) Be sure to kiss your money before you hand it to the teller, because you may never see it again.
Paypal works perfectly well in Germany. If the seller will not sign up for it tell him you are no longer interested in dealing with him. Since this is not an eBay transaction he has no comeback.
Paypal is used in thousands of off-eBay and private transactions every minute. I have used it to contribute to family gift pools. Paypal has strong Buyer Protection. Do not forfeit it.