kidscoach,
i've been researching an upcoming visit to spain that my husband and i are planning and i ran across that miro art logo at the spain tourism agency online. it covers tourism for the whole country and most large cities have tourism offices for the national agency. i'd plug into google search: "spain tourism" and see if you can pull up the country's official website and i'll bet you'll see that logo. i think it is a really cool design for a teeshirt and i'll bet the tourism office that uses it as a logo, can tell you where you could get it the cheapest in teeshirt form.