EyeBuyDirect.com has a large variety of frames and options. You can get UV coating, tints, sunglasses, goggles, safety glasses, etc. You can get simple single vision spectacles custom made to your prescription for as little as $20 (including shipping).
I recently bought two pairs of eyeglasses. One pair was from a large eyeglass store in a shopping center and cost about $260. I bought the other pair online from EyeBuyDirect.com for $42 (including shipping). As it turns out I like my $42 glasses better, I won't be buying any more spectacles from the expensive mall stores.
Of course you still need a prescription (in order to know the degree of correction). Note: Sometimes your normal medical insurance will pay for a periodic eye exam, and you can get your prescription free as part of the exam. My glasses are single vision - not bifocals. Single vision glasses are probably safer to buy online, since the results with bifocals are more dependent on various measurements relative to your eye's pupil. The results with my glasses were great.
EyeBuyDirect.com's website is easy to use. I am a very happy customer.