If its just slight pitting (send a pic if you can) you can use Abranet cloth 400 grit, then finish with 600 grit. Only do the areas that need it, and just enough to remove the pitting.
Use you finger nail to check for smoothness.
Thats how you can do it if you are on a budget, but if you have the pennies then get new forks- also depends on the severity of the issue.