Hi, Lisa.
When I am expecting a girl to come in, when I let her out in the morning, I wipe with a white tissue.
If you do that daily, you will get her on the first day.
As far as books, there are some really good ones, and some great websites too.
I LOVE this website, you will spend days going through all this info.
http://www.lowchensaustralia.com/Breeding.htmThe MUST HAVE book is Canine Reproduction, A Breeder's Guide by Phillis Holst.
2 other very good ones are "Successful Dog Breeding" by Wilcox and Walcowicz, and my longtime favorite, "The Joy of Breeding Your Own Show Dog" by Ann Serranne. Don't let that title put you off, it has one of the best sections of puppy rearing, whelping, etc of all of the books.
If I were you, I would be looking at whelping box designs NOW. Get some ideas together, and get a good one built in plenty of time. Larger breeds like Rotties etc can crush puppies if the box is not made properly. A proper box also gives the mom a place to get away from the pups if she wishes, and later a separate potty area for the babies when they start getting around at about 3 weeks.
I'm attaching a couple of photos of mine that my BF made for me. It's made of that white malamine material that lots of cabinets are made of. Altho it's quite heavy, and BIG, it is wonderful, and I love it.
Another important thing for you to have is a good mentor who is experienced with whelping. They don't necessarily have to be nearby, but having some support there with you in the box the first time will give you a lot more confidence in the future.
How you handle baby puppies in the first 3 weeks, and esp the FIRST week, will have a lot to do with how many puppies survive.
If you have any specific questions about whelping, puppy raising, etc, I will be happy to try to answer them.