Well, based on recommendations from Fodor Forum Folks, I have taken the plunge and will be planning my own trip from Florida to Austria and Italy. I just booked my first hotel in Vienna (DO&CO) thru Hotel.com and the thought occurred to me... How reliable are sights like Hotel.com, Orbitz, etc? I received a confirmation email from Hotel.com, but no payment was required. Can I be confident that I have a firm reservation?

I have not used hotel.com and can't comment on that specific site. But you can always follow up directly with the hotel. I usually confirm with the hotel anyway, closer to my vacation time.

I like to use booking.com site. I have found that to be very reliable and the user reviews helpful. Reviews are only supposed to be made by folks who have stayed at the accommodations. I have not had any problems.

I have used hotel.com in the past, but I had one problem booking a hotel in Strasbourg a few years ago, and I have not used the site since then. I always confirmed directly with the hotel two months before the stay. Lo and behold, the hotel had not received any reservation request from hotel.com. Calling hotel.com help desk ended up he said she said. "They should have received the request. I can resend the request." So he did, and the second one went through. The same room was still available at the same price.

Some say because reservation mishaps have not happened to them, it is not necessary. I always do reconfirm. With email, there is no material cost to verify bookings.

Whatever agency I use, I always bring the confirmation--if only the immediate one, not just the follow up e-mail--from the agency.

Does DYI mean "Do Yourself It"?

No probs ever with Orbitz. If you're really worried about hotel.com (what happened to hotels.com?), then cancel and book through Orbitz or Expedia or similar. Never used etc.com ;-)