A.,
I just want you to know that I really think you are doing everything right.
Potty training is stressful for us moms, particularly with our first, because there is no set formula to use - what works with one child doesn't work for another; what motivates one child doesn't motivate another.
On top of that, children are physically and emotionally ready for potty training at different times - your daughter could be physically ready but not emotionally ready. She could wake up next week Monday and be completely ready.
The best advice is to not compare her to others.
However, I want you to know that almost no mother I know (including myself) has never fallen into that trap from time to time.
All that being said, I would just keep on doing what you're doing - read potty books to her, let her "watch" you go to the potty, be excited about it, have her put her dollies and stuffed animals on the potty and so on.
If you can get her to watch a child around her age go on the potty, that often works wonders - however, again, if she's just not ready, it won't change her overnight.
And while I can totally understand how ready you are to get rid of those diapers, always remember that early or late potty training has absolutely no bearing on success in life.
My nephew wasn't potty trained until he was 4 1/2!! He's now 13, in all the advanced classes, and was just selected based on math test scores to participate in a local college program for talented junior high school kids.
Just wanted to let you know that you're doing a great job, that I KNOW it's frustrating and that this will all come to end some day!! Best of luck, M.