I just bought a pair of eyeglasses from Clearly Contacts with excellent results. I browsed online and used their application where they put the frames on the picture you upload of your face. Not perfect but not horrid either.
I went to my optometrist for a glasses prescrip and I got the important measurement of where your pupils sit right on the prescrip. For the others I just measured a pair of old glasses with a perfect fit.
While I do wear my glasses and see perfectly I will tweak them a little by my niece who works at an eyeglass place repairing and fitting glasses or just go to my local store for this service,
After looking online for over a month I finally called a sales associate and told her a few I liked but also what was wrong with them. She was excellent finding me a variety of similar pairs with the modification I wanted. Couldn't have been happier with the experience.
I've spent a fortune on glasses previously and the quality is the same or similar. I visit my ophthalmologist in a few month and he always checks out that your glasses fit your face properly and the prescription is correct, I believe they all give this service if you happen to see an ophthalmologist.