The major site for making reservations online is OpenTable, which has arrangements with 20,000 restaurants in the U.S. and 17 other countries. At opentable.com, you can search by location, cuisine, time, party size and, if you know it, restaurant name. If there are seats available, it's a simple matter to book a table, and there's no extra charge.
Generally, the restaurants you'll find on OpenTable are upscale establishments, since the proprietors have to pay for the computer system used to interact with the service plus a fee for each booking. Still, if that's the kind of dining experience you're seeking, this is a lot easier than making lots of separate phone calls to find a free table. The service is available on the Web, and there are apps for all the major smartphone systems and the iPad.
The leading restaurant discount service is Restaurant.com, and AARP members are entitled to special savings when they access the service through www.aarp.org/restaurantdiscounts. The clever concept avoids coupon-clipping by letting you purchase gift certificates for participating restaurants (there are roughly 18,000 nationwide) at substantially less than face value. For example, you might buy a $25 gift certificate for $17.50, or $15, or $10. The offers vary from restaurant to restaurant, and you'll generally find restrictions apply, but the discount amount is always significant. You can use the gift certificate yourself, or give it as a gift. And there's no waiting for a mailed document — just make the purchase and print out the certificate.
Local Information Sources
A great way to figure out whether a restaurant you're considering is right for you is to take a peek at the menu. We've all peered into the window to do just that, but it's much more comfortable online. Odds are, if you search for the restaurant name, you'll find they have their own site, or a page on a local group site, with an online menu to peruse in addition to photos and hours of operation.
Another worthwhile resource is your local newspaper's site, where you're likely to find restaurant listings by town and/or neighborhood, along with reviews and additional information.
Finally, there are excellent online opportunities to share food discoveries with other diners in your area. The message boards at Chowhound.com are a particular favorite, with a lively community posting questions, answers and recommendations in localized sections serving the U.S. and Canada. And for nights you want to stay in, the Chow section of the site has an outstanding collection of recipes and cooking tips.