Carol,

I , too , had an ancestor in the 22nd Texas Infantry Regiment. The 22nd was part of the First Brigade of Walker's all - Texas Division which fought in the Trans Mississippi theater. Walker's'Division was initially raised in Texas , near Austin , in late 1862. I don't believe they actually got into the field before early 1863. One of their first goals was to break the Union siege of Vicksburg. I believe their first action was at Milliken's Bend . Let me guide you to a book which has been reprinted and is totally devoted to Walker's Division. It is written by Blessington and is probably available through C.Clayton Thompson books or Guidon Books or a dozen other book sellers who specialize in Civil War books .
Since I recently discovered my ancestor in the 22nd , I've been looking for things myself. If you want me to , as I discover books and articles about Walker's "Greyhounds" (their nickname) , I'll let you know about them.
Let me also guide you to a website which contains loads of information about Walker's Division and theyr activities.
Try Randy Texans site. Let me know if you have trouble finding it. Good hunting . Craig