Nancy,
When you take her to the door, stop and whine a bit yourself and then let her out. It's the same way you'd teach a child a word.. you repeat it over and over. Do this with the dog and she'll get it.
Also, make sure you take her outside on a leash and not just let her out until the habit of going outside is completely learned. Even to pee. I know it will be a pain in the butt at first, but you will benefit greatly in the years to come. As soon as she's gone, bring her immediately back into the house. No playing, no running. She has to learn that going outside is just for potty and thats outsides only purpose right now. After she's gone, praise her and/or give her a treat.
I would also suggest that even if she's going, to say the sentence "go potty, go on go potty" or something similar. Believe it or not, she'll pretty much go on command after awhile when you say that. Very useful on cold nights, rainy, snowy, vacations, or when she's just plain distracted.
My girlfriend decided because I had mentioned liking Great Danes, that I just had to have one. Mind you I had not ever owned a dog before. Luckily, a friend from high school is a certified dog trainer and owns her own do-it-yourself dog bathing and grooming shop in Livonia. Although he was too big and too dog macho to be calm through the classes, I took the sheets home and found it very easy to train him as long as I was consistent.
Lastly, watch the circling or if she's staring at you. She's probably giving you "I really have to go" signals that are easy to miss right now since she's new to you.
I would love to talk with you, so if you'd like to email me we can exchange numbers. Good luck with everything and if you need me, I'm here.
L.
____@____.com
PS
although I spoke about whining at the door.. I didn't know about bells at the time. The choice is yours, the method is the same.. you have to do it every single time to show her and she'll pick it up :o))