I moved from Washington to Texas in September, but have found that I do not like it and want to move back. However, my (soon to be) ex does not want to return, and will not let me take the children with me. They want to keep them solely to get child support. What are my rights and how can I be able to return with at least one of my children? Are there any free legal aid or access centers that can help me file and tell me what I need to do?

You could move back to your home state and file there if nothing has been filed yet and ask the courts for custody. Your under 6 months in Texas.

Texas Divorce Laws

Washington still could hold jurisdiction.

If you return to Washington before 6 months has passed since your move to Texas then you could litigate the custody issues (and support issue as well) in a Washington court. If you stay in Texas you'll have to litigate there. You've got a unique opportunity to lock in jurisdiction in Washington so don't neglect that as a major issue (time is running out on this as an option, however).

Don't expect to be able to split the kids up in a custody battle and the ultimate outcome is too variable to give a reliable answer based upon the information you provided.