I personally use a small coffee grinder and yes this is it's sole function. However, you can also use a good mortar and pestle. IT will take a little longer, but you can control the coarsness of the grind a little better than with the grinder in my opinion.
We use both a small cheap Black and Decker blade type coffee grinder for small batches and an inexpensive blender for larger batches. Both are dedicated to grinding spices only. If you can, make sure the blender has a glass jar. It won't retain odors, stains or get cloudy from grinding hard spices.
Got our blender at a thirft shop for $3 Bucks.
We also have a less expensive food processor to puree' BBQ sauce and my homemade hot sauces. Seems the habanero's like to leave a little tingle behind on the plastic bowls and the next batch in the machine got a little interesting.
I use a mortar and pestal also have a grinder thats really more like a shredder (mainly works on rosemary and woody/ viney spices and herbs. Cheese graters also work well for many spices.
Check this site out for good spices and accesories. A coworker of mine has delt with these folks for several years and vouches for their service.
If it aint broke, Break it!
Then rebuild it better.