From within AdWords you can use the Traffic Estimator or the Keyword tool which will show you the estimated C.P.C.
Exactly what he said, however started out with new ads you will often have to pay a much higher price until you start receiving some clicks and maintain a high quality score.
these are estimates based on the average quality score, no tool can tell you the exact CPC because there's no way to tell what your QS is and what competitors bid (and their QSs respectively). The only way to see the real CPC is run an actual ad. Other than that traffic estimator is as close as it gets.
I'm not an AdWords user nor an experienced one. But I do know that the more advertisers (more number of ads), the more you would have to bid (pay more for higher ad price).