Karen, you can shim the levers yourself by inserting a small piece of adhesive-backed "stuff" -- so technical, eh? I use FeltGard Heavy Duty Felt Pads (they're intended to put under furniture on hardwood floors to prevent scratching).

To insert, open up the brake lever the same way you would when you apply your brakes. insert the felt (adhesive side down) and then close the lever again, depressing the felt pad to create adhesion.

Note that depending on how your brakes are adjusted, you might need to open them up just a bit after shimming. Spin the wheels (off the ground) and if the brakes are too close to the rim, use an alan wrench to slack a little bit of cable.

BTW, which model levers do you have (they probably have it printed on them). Sounds like older 105 or Sora.