Most people find the easiest and most cost-efficient way to get to Lake Tahoe is to fly in to Reno, and then either rent a car or take a shuttle to Lake Tahoe. The drive from the Reno airport to South Lake Tahoe takes approximately one hour, 15 minutes.
Reno Airport.com - Several airlines fly in to Reno-Tahoe International:
Flight Information - Updated travel info from the official airport website
Tahoe Packages - direct to
Travel Deals - specials and deals are available
Cheap Flights - offers promotional flights
Travel Packages - its possible to find cheap hotel and air packages
If you would like to fly direct, Lake Tahoe does have a (very small) private airport, which is located in South Lake Tahoe. This is mainly used for small private planes.