Arbiter can handle that for you in a limited way. Login to your Arbiter account and click the BLOCKS menu item. Next, click on the Sites sub-menu tab. Make sure Show All is checked. Check up to 3 sites where you do not want to receive assignments.
Also, make sure you have your travel limits set correctly. The assignor will not assign youth referees to games outside of their general area unless specifically requested. For example, if you are a youth referee and live in Boise or Meridian, it is unlikely you would be assigned games in Nampa or Mountain Home unless you are playing a game in that area. Because of the way Arbiter calculates distances, it is recommended that referees never set their travel limits to less than 40. If you do, you may find that you do not get any assignments. Please trust me on this.