figure out what you want to do with the car first. Swaybars will let you keep a softer ride cruising the Hwy, yet help keep the car flat in corners, but will lift the inside front wheel accelerating out of a corner= wheel spin.
Factory parts:
Mk2 with sway bars, look under a Golf GTI or Jetta GLI or 16V
Mk1 with sway bars, look under Rabbit GTI, or Scirocco 8v and esp. Scirocco 16V. Factory clamps to the cross beam and trailing arm tube. Aftermarket clamp to the cross beam and have a bracket to the lower shock bolt.
Aftermarket look at Neuspeed, Autotech, google search
For race/autox there is some dispute between a big front bar setup and no bars at all, depending on power levels. I personally don't like much bar on the drive wheels, tuning with spring rate and shocks.