Perhaps you can describe the problem in a little more detail. Are you
talking about the parking brake or the regular brakes? Front, rear or
both? What exactly is sticking? Do they ever become unstuck?

Oh, and don't expect an answer in 20 minutes, no need to repost your
question.

I think you need to purge the whole brake system, change the whole fluid!..

Is the fluid dark?...When was the last time you purged your brakes?...

As a do it yourself thing (one man bleeder job) I'll suggest you to do the
next:

Buy one of those "speed bleeders" http://www.speedbleeder.com/ and even if
you don't find the right size for your calipers it won't matter.

Attach a a nice piece of clear tubbing (like the ones used for aquarium
pumps) on to the threaded part (bottom), be shure to attach or clamp it w/a
piece of wire, so when you step on your brakes while bleeding, your tubbing
won't get popped out of the "speed bleeder".

Then the other end of the clear tubbing gets attached to the bleeder screw
that you have on your caliper, and be shure to attach it well with a wire
too!..

The "speed bleeder" has a little ball inside that allows you to pump the old
fluid out, and doesn't allows the air to get back into your brake system.
This is better than any other device you could buy at any place to purge or
bleed your brakes!...

Just be shure not to leave your brake fluid reservoir with out brake fluid
or you'll end buying a new brake master cylinder...