While I agree with the optician's advise to do it in person, my bargain hunting side will advise you to use this outfit which ships direct from Italy (they source direct from Luxotica, which owns Lenscrafters and manufactures about 90% of the glasses in the market). My wife and I have about 15 pairs of glasses from them, mostly sunglasses but four or five are eyeglasses. If you know your prescription, they can fill it for next to nothing, if not, buy the frames and take them to your local shop to get the prescption lenses. Service is outstanding, prices are at least half what I would pay here in NYC ( my wife regularly buys $300-400 Chanel's from them for $150 or less). If you have a pair of glasses, you can compare the size, by measuring them in millimeters, to what they are selling. For me, the huge savings was worth the risk of not having the frames be right for me (they do have a return policy though). I can't stress enough how happy we are with them.www.giarre.com
Email them before you order and ask them to send you their 5% off coupon.