I love the NROL4W book... it really helped me get into the gym and start lifting free weights. It is an excellent place to start, and, combined with some other resources, you should be able to learn some decent form without hiring a personal trainer. Getting a trainer is always best, but not all of us can do that.
I am a huge fan of lifting free weights instead of machines... but everyone needs to find what works best for them. Personally, I like the fact that I can get a full-body workout from just a few exercises, and I think a lot of benefits come from muscles working in conjunction with each other to balance and maintain form. Plus, lifting big free weights makes me feel like Wonder Woman... and who doesn't want to feel like Wonder Woman?
Here are some links to resources that really helped me:
Stumptuous "Dork to Diva" series www.stumptuous.com/category/training/dork_
Stumptuous "Lurn to Squat Good E-ZY" www.stumptuous.com/lurn-to-squat-good-e-zy
Stumptuous Learning the Squat series www.stumptuous.com/learning-the-squat-1-de
YouTube Squat Rx series by johnnymnemonic2 www.youtube.com/playlist?list=PLC03D688F10
Currently, I'm using a different program called "Beautiful Badass" by Nia Shanks. Nia's ebook has less detail than NROL4W, but has a good selection of different workouts and uses a slightly different program philosophy of 'more sets, fewer reps' which works well for someone like me who wants to lift as heavy as I can without sacrificing form towards the end of a long set. Also, I like her no-nonsense philosophy: www.niashanks.com/2012/10/rid-your-life-of
Even though I like Nia's program better for me, I would still recommend New Rules of Lifting for Women for any woman who wants to start lifting.
Hope this helps!