Do I owe support on kids thatI never see or even know where they are?

Child support and visitation are separate issues.  You still owe child support even though you haven't seen the kids; however, since you are out of work, you may be able to obtain a reduction in child support due to changed circumstances of reduced income. 

You have a right to visitation.  The court can set a visitation schedule.

You will need to file an Order to Show Cause (court form) requesting a modification of child support and modification of visitation.  File the Order to Show Cause with your declaration signed under penalty of perjury stating the facts supporting your arguments for modification of child support and  visitation.  When you file the Order to Show Cause, the court will set a date for a hearing on these issues.  File the Order to Show Cause and declaration with an attached proof of service.  You can either use a court form proof of service or you can write your own.  The proof of service verifies the date of mailing the documents to your ex-wife.  If you write your own proof of service, it would just say that you are over 18 and the attached documents were sent via first class mail unless otherwise specified to ____________ (name and address of your ex-wife) on _________ (date).  You sign and date the proof of service under penalty of perjury at the bottom of the form.  The date you sign should be the same date as the date of mailing and the same date you file the documents with the court.