As a doula for the past three years, I am ecstatic to see the responses here!
It makes me feel very proud that our training is respected and sought out by others in the birth community, ESPECIALLY nurses.
Why not open the door to the birthing world and experience it from another point of view? Experiencing birth as a doula for a few births, and NOT as a nurse (NO clinical duties or paperwork) would EMPOWER you as a nurse and I definately think it would give you a huge advantage with your patients!
I know there are things EVERY nurse will learn at a doula training. Don't get me wrong--I LOVE you OB nurses, and you know SO much! There are just so many tips and tricks that may help you in the delivery room. In fact, at a recent birth I attended, we had a fabulous nurse who had been in L&D 5 years, however had never heard of "tug of war" pushing! I was shocked at first, but then I realized.. if she had never seen it or was shown it by a coworker, how else would she have found out? It's not a huge thing, but I'm trying to use it as an example of one of the things I learned at doula training.
Oh, and ALACE is good. There are a few certifying doula organizations. DONA, CAPPA, ALACE and GBI (Global Birth Institute) are the most popular, IMO. ALACE is reputable and based in Boston, MA. Also, you DO NOT have to become certified as a doula to attend births as a doula. Doulas usually start attending births after they have completed their training with one of the organizations. Certification is merely a choice, doulas are not regulated or governed, because they don't do anything clinical or wouldn't be in a position of liability.
Yikes, sorry for that long post. Hope I was helpful in some way.