What is it that you are trying to write to as I can see if I can be of any assistance.
It seems that Zac has put up his house for sale in Las Vegas but what you might wish to do is to visit the house address to see if he might be still living there or someone who is the real estate agent who can then let you know more if he is in town. No guarantee that he still lives in Vegas as the article published is accurate about him selling his home. Contacting those within his agency would be the best bet to reach him.
Also if not already, follow his twitter page as it will sometimes say where Zac will be hanging out in Vegas if he is in town.
I hope the suggestions listed will help in planning for a meeting. If you could take a moment to rate my assistance so that I can receive credit for helping you today.