My ex wife has informed me that she wants to move to another state with my two children ages 5 and 9.

Like I stated before there are factors into considering the move. It is "presumed that the move will be allowed." The person who stated that she has custody she can do it is incorrect. You can obtain an attorney but one is not needed. And YES you can obtain custody if she leaves the state without filing as you seem to believe she intends on doing. She has to file relocation paperwork with the courts and have a new parenting plan before she leaves. The ONLY way she can leave is if she had seen it as unforseen ...or their life is in danger. She can leave for a job but that doesn't mean she can take the kids while the motion is ongoing. She leaves this state with those children ...without going to court first to have it allowed (if you file)...then she is contempt of court..ask any attorney. They will tell you the same thing. Plus 80% of the time it is not because "of a great job." I won custody of my daughter three years ago because my ex wanted to go to school and her hubby had a job in CA that was offered...I won...she didn't leave...and the rest is history.