My column two weeks ago about how I used the Internet to plan a vacation in Europe brought several helpful responses from readers, including travel agents and a handful of travelers who do their own planning and booking online.

Two readers suggested Web sites that I have not used, and one offered a critique of one of the sites I said I liked, www.tripadvisor.com (more on that later).

Two travel agents complained that I dismissed the role they can play in a successful vacation. As I said, I didn't use an agent for this trip for two reasons: I enjoy doing the work involved, and it helps me do my job by providing me the same experience many of you have these days.

Travel agents usually charge a fee for booking an airline ticket, an average of $37, according to the American Society of Travel Agents. But agents don't normally charge for booking cruises, package vacations, hotels, or rental cars, because they still earn commissions on those.

The most useful response I received was from Kate DeLosso, a Delaware County agent who works from home for Travel Counsellors, a Saddle Brook, N.J., agency. Here's what she told me in an e-mail:

"Read your June 8 column with a good deal of nodding and head shaking, probably because I am one of those travel agents. There are more and more people who are taking your approach and for that I say: Thank goodness. When folks know where they want to go and where they want to stay, nowadays they do not need a travel agent. But there are times it would be a good idea."

For an agents' networking group she belongs to, DeLosso put together a list of 10 reasons to use a travel agent:

1. You are planning a special-event trip and want everything to go absolutely right, but don't even know where to start.

2. You are thinking of traveling to an unfamiliar destination.

3. You are planning a family reunion, and everyone has a different idea of where to go and what to do.

4. You are booking a cruise.

5. You need an international airfare, and you have been shocked at the prices you are finding on the Internet.

6. You are planning the dream once-in-a-lifetime trip, or the itinerary you are planning is complex, and you need a real person to help you.

7. You don't have the time to do the research.

8. Or you have done extensive research, and you are now more confused than ever.

9. You are traveling to a "difficult" country and don't know if you need a visa, how to get a visa, and what to expect.

10. You are simply not comfortable booking on the Internet.

DeLosso reminded me, too, what numerous agents have told me since the airlines stopped paying commissions in the mid-1990s and they were forced to change their business model. They specialize in niches in the travel world, gaining knowledge and expertise that their clients value.

DeLosso specializes in travel to Asia, particularly for those who were adopted from Korea or China by American parents and want to find out more about where they were born and who their birth parents are. She has two children adopted from Korea.

"I focused on places people were not comfortable planning a trip on their own," she said.

The additional information I learned about the TripAdvisor Web site is how the service, a division of the Expedia online travel agency, has to closely monitor reviews of hotels to make sure they're from real travelers and not a hotel's public relations department.

In fact, to maintain credibility, all hotel-booking Web sites need to keep a close watch on reviews from "customers" to guard against those who would try to game the system.

DeLosso suggested following a rule of thumb that I have adopted myself. If eight out of 10 reviews are good, that hotel is probably a safe bet.

I would add: Be careful if most reviews of a hotel on any site are mediocre, and one is glowing and over-the-top.

Finally, a word about another topic covered in the column two weeks ago: How do I get the lowest possible airfare if I'm doing my own Internet booking?

In my case, I know I didn't, because I bought tickets at the end of February, and demand has been so weak since then that fares have gone down.

Bing Travel (www.bing.com), the new name for the Farecast price-forecasting Web site, says average international roundtrip fares are down an astonishing 33 percent from where they were last year.

So for the consumer, it's a great time to be able to take a trip abroad.

If you're an airline, of course, you look at it as Kevin Crissey, the industry analyst at UBS Securities, does. In a recent report to investors on one carrier, his headline was: "Revenue environment remains hideous."

Contact Tom Belden at 215-854-2454 or tbelden@phillynews.com.