Welcome to the Guild Kim! Well, I know of no simple mapping program for city maps. It's pretty much a bear of a project no matter what software you are using. There are some CC3 tutorials available in the tutorials section, most of which are available in pdf format here. As to creating regional maps, some members here use CC3 software, others use Fractal Terrains 3 (or Wilbur, a free to download program), but probably the majority of people here use Photoshop or GIMP (some also use Illustrator or Inkscape or sundry other miscellaneous graphics programs). Consequently, most of the tutorials here are written for PS or GIMP, the latter of which is as free to download program. My suggestion would be to explore a few of these tutorials to get a feel for what sorts of map styles you can create with them and then start there. Best wishes.

Cheers,
-Arsheesh