Sometimes it is cheaper to fly RT to LAX, rent a car (e.g. on Priceline.com), and drive the 5 hours each way through the desert, which might be well worth the trip if you are from the UK and have not done this before. Or, fly RT to LAX and fly LAX-LAS-LAX via, say, HP, WN, or AA, the 45 min flight is about $39 each way with an advance purchase (you can check your bags through via HP or AA, but not WN). Even within the states, to fly from the east coast RT to LAS often costs more than the same RT to LAX -- on the same (HP) airplane which stops first in LAS!! They figure if you are flying to LAS then you have $$ to burn....