7. "Our e-mail is a black hole."

Visiting a store often comes with the promise of a salesperson or two at your beck and call, but online customer assistance can be a challenge. It's not for lack of options; e-tailers often offer FAQs, e-mail and live chat sessions. But knowing which works best isn't always so simple.

For example, e-mail is particularly slow, with response times averaging more than 22 hours, according to The E-Tailing Group, and consumers seeking assistance don't want to wait that long. Experts prefer live chat, as reps can steer you to specific parts of the site by sending you direct links.

If all else fails, you can try reaching customer service by phone -- if you can find the number. But don't expect a human being at the other end. (Visit GetHuman.com for instructions on navigating the electronic phone trees of many companies.) Another way to go is to stick with online retailers that make customer service a priority. An IBM Institute of Business Value study found that QVC.com, J.C. Penney and Amazon were regarded as tops among consumers surveyed.

8. "We're an eco-disaster."

Though shopping online sure is convenient, it isn't exactly green. River Vale, N.J., technology architect David Kozinn says that when he ordered a USB drive from Dell, the thumb-size gadget arrived in a massive box stuffed with packing paper. "It's just asinine," he says. (A Dell spokesman says the error resulted from a third-party supplier's assessment of package size; he says the drives are now shipped in envelopes.)

And when Tim Curro from Royal Oak, Mich., ordered a single DVD from Warner Home Video, it arrived in a box big enough to fit 15. (A spokesman for Warner says he couldn't track the specific order but that it "would have been because our fulfillment area was temporarily out of stock on the normal packaging and we didn't want to delay the order.")

Overpackaging -- often the result of retailers relying on standard-size boxes to ship goods they buy in bulk from manufacturers -- isn't just a waste of trees; it can also take up more space in delivery trucks, requiring extra trips and extra fuel. But because companies don't feel the pain financially, thanks to shipping fees, there's not much incentive to change, says Bob Lilienfeld, the author of the Use Less Stuff Report, an online newsletter covering waste prevention. What can you do? Some retailers such as Amazon let you have all your purchases shipped together.

You can also buy carbon offsets for the shipment (one source: nonprofit Carbonfund.org). "It's kind of an after-the-fact option," says Collin Dunn, a writer at Planet Green, an eco-lifestyle TV network. "But every little bit helps."

9. "Loyalty will get you nowhere."

You'd think being a repeat buyer at your favorite website would get you a little something in return. After all, the hardest part of being an online merchant is drawing customers, PowerReviews' Shaffer says. But that's not the norm.

In fact, less than 15% of online retailers offer exclusive deals through their e-mail lists, according to the Email Experience Council, an e-mail marketing company.

To keep yourself on the receiving end of discount offers from an e-tailer, an inconvenient but effective strategy is to start a new account, using a different e-mail address and credit card. New customers get treated to appealing introductory offers because companies are trying to make a good first impression, Shaffer says. To find a whole range of new-customer deals, visit DailyeDeals.

10. "Don't like our prices? Come back in five minutes."

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The ability to update websites on a whim has given free rein to retailers with itchy pricing fingers -- amounts can fluctuate 10% to 15% in a week, says Darren Davis, of PriceGrabber. What's the point? Retailers are watching each other in order to match prices and stay competitive in the marketplace, Davis says. If they don't, customers could flee to cheaper pastures, which they can find with just a click of the mouse.

Your best bet for zeroing in on the best deal is by taking advantage of price-comparison sites such as PriceGrabber and NexTag, which get paid for steering consumers to merchants. The sites also offer price alerts, letting you set an amount for an individual product and receive an e-mail if and when the price hits your target.

Cybershopping not your idea of a good time? Since online deals are often better than what you'll find at the mall, you can use the Internet to get a better price from a bricks-and-mortar retailer, says Bell, of DealHack. Simply print out the offer and ask a local merchant to match it.