The rate of nearsightedness in the United States has rocketed 66 percent in the last 30 years, which means more Americans are shelling out for eyeglasses and contact lenses.

A study in the early 1970s showed that 25 percent of the U.S. population ages 12 to 54 suffered from nearsightedness, or myopia, which means they have trouble seeing things at a distance. A more recent study, from 1999 to 2004, showed the rate had soared to 41.6 percent. Americans spend $31.7 billion annually on vision products and services, according to the Vision Council of America. Eyeglass frames and lenses make up the largest portion, about $21 billion.

Customer-satisfaction surveys show that consumers are generally happy with buying eyewear from their eye doctors or from optometrists. But to save big bucks, you'll have to consider shopping at unconventional places. For example, some online stores sell custom prescription eyeglasses for about $8, instead of the hundreds of dollars you're used to paying.

Here's what you need to know:

Eye health is a priority.
Studies show consumers who order contacts online tend to get fewer eye exams, said Dr. S. Barry Eiden, immediate past chairman of the American Optometric Association. "Regardless of where you buy eyewear products, you should put your eye health first," Eiden said. The good news is that buying products from alternative sources is not a health issue. "If your prescription or the grinding of your lenses is significantly off, you will know it, so you can get the problem fixed or, if necessary, start again with a new pair," says Consumers' Checkbook, which rates service providers. And boxed disposable contact lenses of a certain brand and prescription should be the same no matter where you buy them.

Contact lenses online.
This is the primary way to save money on contacts. And it's easy because you just buy the exact brand and prescription your eye doctor recommended after a proper eye exam and fitting. Such online sites as 1800contacts.com and VisionDirect.com allow you to easily plug in your prescription and order with a credit card. Personnel at the retailers contact your eye doctor to confirm the prescription. Because prices are posted online and products are all the same, it's easy to shop among several retailers to get the best price. Lesser-known sites, such as CoastalContacts.com, WebEyeCare.com and CLEcontactlenses.com, might have lower prices. The regular price of a box of Acuvue Oasys lenses recently ranged from less than $22 per box at WebEyeCare.com to about $34 per box at 1800contacts.com. Buying online also saves you a trip to the doctor's office because the contacts are mailed to your house, and it could save state sales tax.

Glasses online.
Such sites as ZenniOptical.com, EyeBuyDirect.com and CoastalContacts.com sell made-to-order prescription eyeglasses — frames and lenses — for less than $10. Most glasses are in the $20 to $50 range.

But there are several drawbacks to buying online. First, you probably have your eyeglasses prescription, but you might not have the measurement for your PD, or pupillary distance, the distance in millimeters between your pupils. Online sites suggest asking your doctor for this measurement or measuring it yourself. Another drawback is you can't try on frames, although some sites allow you to upload a photo of yourself and "virtually" try on frames. And after you get your glasses, you won't have an optician to adjust the arms and nose pads for a custom fit. Many bricks-and-mortar opticians do that for free, but it's unfair to ask them for adjustments when you bought your glasses online for cheap, Eiden said.

Online merchants are aware of the drawbacks of buying glasses online, said Rob Long, U.S. manager for CoastalContacts.com, whose site sells glasses starting at $6.99. That's why they offer some supercheap glasses — to encourage people to try ordering them online. "A lot of customers will buy glasses online as a backup pair," Long said. "That's their initial intention." Online glasses sellers typically have liberal return and exchange policies, says Consumers' Checkbook.

Reviews of some online retailers are available at EyeglassRetailerReviews.com and GlassyEyes.blogspot.com.

Eye doctor and local optician.
Neighborhood opticians and eye-doctor offices won most categories of customer satisfaction in a 2006 survey of 92,000 readers of Consumer Reports magazine. They were tops in service and selection. Where they rated lower was price. But consider that doctor offices might accept more vision insurance plans than other outlets, Eiden said.

Warehouse clubs.
Costco, Sam's Club and BJ's Optical achieved top marks for price in Consumer Reports' survey. Costco also earned a high mark for service. These clubs might be a good compromise for people who want to buy from a physical store but pay less.

Chain opticians.
Speed is the primary advantage. You can get complete glasses in about an hour. But they tend to be pricier than other options, according to price surveys by Consumer Reports and Consumers' Checkbook. It could be worth paying, however, if you broke your glasses and need replacements quickly. You might wait weeks for delivery of eyeglasses from an online site. And LensCrafters, in particular, has liberal return and exchange policies, said Consumer Reports. Ask about discounts; AAA members receive 30 percent off eyewear at Sears Optical, Target Optical, LensCrafters and Pearle Vision, according to AAA.

Tell your kids to go outdoors and play. Recent studies suggest that children who spend more time outdoors are less likely to develop myopia, said Susan Vitale, a research epidemiologist at the National Eye Institute. "Results need to be replicated," she said. "But I can think of a lot of good reasons to encourage kids to go outside and play."