Not sure I understand... but it sounds like you just need to get yourself a signed certificate. Try going to www.freessl.com.
The name is a little misleading. I don't think they actually offer free certs. But you can pay like $50 and get a cert that is signed by a reputable authority and will be valid for 1 year. This way, when your server presents the cert to the client, they will already have knowledge of the cert authority and the end user should not see any warnings.
If you dont want to pay the money, I think your only option is to sign the cert yourself and live with the warning messages on the clients end. They will still be protected by SSL, but the warning may give some people (read: inexperienced users) some concerns.