The Mandala Lady:
Most people ask this question because they want to know what ones to use to be able to get the bright colors that they see in my colorings.
I use what's called an "artist quality" brand pencil: namely Prismacolor. Several brands of artist quality pencils exist that are equally as good (or maybe even better) such as Faber Castel, Derwent, Lyra, Staedler, etc. For me, I find the Prismacolor pencils blend the best for the style of coloring I do...burnishing.
With quality pencils, the price goes up dramatically from your typical brand of color pencil that you see in most stores...which tend to be chalky, a lot less vibrant, and lack any real blending capability. On average a 12 set of Prismacolor sells between $10-18...while a 12 set of the typical brand sells between $2-3.
For a really good in-between brand, that gives you good color and better blending, I recommend Prang color pencils...which you can usually buy between $4-6. Locally in Corvallis I've seen them at Bi-Mart, Creative Craft and Frame (Kings & Buchanan) and sometimes at the office supply stores.
Another option would be to go to an art supply store where they sell Prismacolor pencils (Creative Craft and Frame carries them). Chances are they sell them as individual pencils ($1.50-$2 a piece) as well as in sets. Buy just a couple of individual colors just so you can try them out and to experience the difference between the $2 set of pencils, the $5 set of pencils, and the artist quality pencils.
The Mandala Lady