There is a shuttle at the Reno airport called South Tahoe Express. It costs around 45 dollars or so round trip. Tahoe is about 55 miles from Reno.
Tahoe is a definite must. BTW - if you stay at Harrah's Reno - I really like the West tower because it is easier to find everything. The layout is kind of confusing because the East Tower has a small casino with quite a few tables and a few slots but to get to the bigger casino and eateries you have to walk across the casino- take the escalator up (see the buffet) then take another escalator down back to the west casino.
El Dorado (across the street from Harrah's-sort of) has the best Friday nite seafood buffet that I have ever had.