‘My son moved with his mom to Texas from California and she doesn’t want to give me their new address. Can she get in trouble for hiding my son from me?’
Assuming that you have a court order allowing you time with your child, if she is withholding your son from you during the times that the order says he should be with you, then she may be guilty of parental kidnapping.
In addition, if California has jurisdiction (for example, if your court order is from California), and if she moved away from California without first obtaining permission of the California court, you can file an action with the court in California demanding his return (and requesting temporary custody, if need be).
If, however, you have no court order at all, then she is not yet guilty of anything, and you will need to file an action with the court, and asap before she achieves residency in Texas, at which point the Texas courts may take jurisdiction.