Hi there, Beverly!
The
dining pages on the
Walt Disney World site offer, as you noted, a range, but do not give specific details. The reason for this, I was told, is because prices can (and do) fluctuate with travel seasons, and it is easier for accuracy to provide a consistent, stable range of prices rather than attempting to keep pace with the changes, some of which affect all of the restaurants, some of which only a few, etc.
You'll find a variety of fan sites, unofficial and unaffiliated with the Walt Disney World Resort, that rely on Guest information to keep pace with the changes. A Guest will submit pricing and menu information, and the site owners will fact-check for accuracy before posting.
One that I use on a regular basis is www.AllEarsNet.com, which features both prices and full menus. Again, these are not under the umbrella of Walt Disney World, so they cannot be held as "gospel".
If there is a a restaurant in particular that you'd like some assistance with, please drop me a line or give a call to (407) WDW-DINE. The Cast Member have the most current pricing information for all of the restaurants, and are always happy to provide that information to their Guests.
Have a wonderful time!
See you later, celebrator,
-Deborah B.