Complaint Review: Northwest Airlines

In October 2005, on two occasions, my NWA flight was overbooked. Northwest agents offered a free round trip ticket, good for one year, to travel anywhere in the continental USA. I have been attempting to make use of these E-Transportation Travel Vouchers since early December 2005.

Every attempt has met with "There is nothing available on that date to that location". I attempted to locate available flights not only to destinations considered Prime locations, but also to cities, such as Chicago, Detroit and Minneapolis, Omaha, etc. No availability could be found within a 45-day period before or after my requested dates and destinations.

I feel that I have been the victim of a Fraud Perpetrated by North West Airlines.
I was duped into accepting a worthless piece of paper to make it easier and less stressful on Northwest gate agents who then did not have to deal with an irate customer being involuntarily refused a paid for seat on that flight.

I was told that I was being given a Certificate good for a free round trip, anywhere NWA flew in the continental United States. That is not what I was given. I received a highly restricted, worthless piece of paper.
Northwest Airlines states the voucher contains the words " good for one free coach roundtrip ticket in W class/ seats are limited." That is true. The voucher does not explain what Class W is nor does it define "limited."

I was told by Northwest their agents are too busy to go into detail regarding the "free ticket". How much time would it add to say free ticket with extremely limited seating?
I believe Northwest airlines' "free ticket policy" is fraudulent.

Charles
sterling, Virginia
U.S.A.