According to the research I've done, the only WI-FI hotspot in Las Vegas is at the Four Seasons (Mandalay Bay). I haven't tried to see how far way you can connect, but I understand it's intended for hotel guests only.

High speed internet connections are only recently beiginning to be available in Las Vegas hotels. I've found CAT-5 wiring and connectors only at Caesars Palace and the Venetian, and then not in all rooms.