I kissed a frog in Sparta, Wisconsin. Voluntarily. Enthusiastically. The frog in question is one of hundreds of giant fiberglass molds scattered across a football-field-sized lot behind a nondescript sheet-metal building off County Highway Q. This is the home of FAST — Fiberglass Animals, Shapes, and Trademarks — a company that has been building giant roadside statues, mascots, and water park attractions since the early 1970s. It was incorporated under its current name in 1983 by a man named Jerome Vettrus. FAST has worn the mantle of American titan-builder for over 50 years. Among their greatest hits: a 200-foot-long sea monster at House on the Rock in Spring Green, Wisconsin, and a 145-foot-long muskie in Hayward. After each job, they keep the mold. All of them. For decades. And that's how a quiet field in rural Wisconsin became one of the most unexpectedly wonderful places I've ever wandered. There are giant skulls and colossal dogs, oversized Santa Clauses and titanic mice.…