In addition to the boycott of Cinco de Mayo comes this post from Texas
sources:

TO EVERY AMERICAN CONCERNED WITH THE ILLEGAL INVASION OF
THE UNITED STATES BY 20,000,000 MEXICANS WHO HAVE COME
TO THE UNITED STATES TO TAKE AWAY JOBS AND SOCIAL PROGRAMS FROM THEIR
RIGHTFUL OWNERS : THE AMERICAN CITIZEN!

"The invasion of Mexican illegals and their local supporters in the
United States have had the effrontery today, to replace with a
different version our National Anthem. This they call it the version
of the "New America's Hispanics Anthem" If you don't want to lose
your country to Mexico... You need to join us in our efforts to
BOYCOTT THEIR TRAVEL INDUSTRY. Mexico is largely dependant on the
tourist industry geared towards the American dollar and to achieve
that they spend zillions to get Americans there.

For one year, beginning May 1, 2006, no self respecting and true
American Citizen will book a vacation to Mexico until May 1, 2007.

There are many cruise packages you can take which do not include
Mexico, even if the advertising agency call it the "Mexican Riviera"
Best if you think of them as "dysentery ports". We can live without
visiting a place whose government is clearly trying to take over our
country.

Please let your travel agency know that you would be interested in
going to the Caribbean, Bahamas, Costa Rica, Panama, but you will not
be going to Mexico this year... until that country understands that
they cannot overtake the Unites States in any form or shape.

Please GET ANGRY and fight back!!! Show Mexican illegls and their
promoter, Vicente Fox, a little of our good old American Muscle!!!