I agree with Stina that you should try to speak to your children regularly by telephone.
Take a look at
Child Support Obligation Calculator - Virginia Department of Social Services for estimating your child support, and pay what you can -- always by check. This is good for your kids, and shows the court you care.
Ask mom for alternate weekends, alternate holidays, and half of summer; with visitation handoffs at an I-81 rest stop outside Winchester (half way between you).
If you don't get that much visitation or close to it, you need to go to court soon. The longer you wait, the less visitation you may qualify for.