For beginners I would suggest either the Staedtler or Faber Castell brand of pencils. These produce significantly better results than bargain bin pencils, provide good colors and allow you to try some simple shading and blending techniques. With practice the best coloring results can even be achieved with the most modest tools!
A few years ago, I wrote a book about realistic crayon drawings. What a joy it was to create, for I had brought my childhood dream into my adult professional life. I wanted to share it with others, for few knew that crayons are actually a wonderful fine art medium. They're not just for kids!