I'll preface this by saying that if you really just want to be in and out of the chapel and are not particularly concerned with the vows, how much or little religion is incorporated into the ceremony, how much or little humor is incorporated into the ceremony, etc. then you're probably fine booking any officiant your chapel would have otherwise scheduled you for. Most Vegas chapel-affiliated officiants have done so many ceremonies that they'll be able to make the ceremony seem somewhat personal even if they only meet you for ten minutes before the ceremony starts. They'll be able to keep to the above criteria fairly easily even though they don't really know you.
Second word of wisdom; most chapels will require you to use their officiants. So, if that's the case, you may have only a small selection of options, and you may also have no way of reviewing them beforehand, rendering this article useless to you.
So, with that out of the way, the best way to find an officiant if you have exact criteria you're looking for, would be to post everything you can about what you want in a thread on the TK Vegas section at http://forums.theknot.com/Sites/theknot/Pages/Main.aspx/local-wedding-boards_nevada-las-vegas and also dig around the officiant section of this website, which will slowly but surely be growing as more come recommended or receive positive reviews and I add them. Chances are between the two sources we can find you an officiant who meets your needs.
There is one other way to narrow down your search. If you're getting married at any of the resorts where Cashman photography has exerted their monopolistic power to force you to use their videography services as well, there is actually one useful thing that has come out of that, which is you'll be able to watch that resort's officiants beforehand using the following procedure:
the good news is there's a way you can watch ceremonies at those resorts IF the people getting married paid extra for the live video feed of their wedding. Here's what you do: