I am looking for a short story, poem, or chant to introduce/exhibit the "I have" pattern to an elementary level ESL classroom (as in, I have a T-shirt. I have brown hair.) I don't have access to any English books right now, so a website or an explicit example would be ideal!

You can browse it for free and use most of the stuff. Be sure to book make it I use this site for my foster kids. WELL worth the money for one year membership. Just save what you want in a folder on your computer for future references.
Definitely would recommend this site to everybody.