Where is Shamrock, Texas? Where does one eat in Shamrock, Texas? Drive out East of Amarillo on Interstate 40, and you’ll run smack dab into Shamrock. The luckiest place in Texas? Maybe. If you find your self in Shamrock, why not try the The Roost? Good old fashioned American food, Sandwiches, even Seafood, Have a look at their menu down below!