I bought a small package of long pepper in Colcatta, India, and put them in a table grinder. I use them just like regular black peppercorns.
I realize this doesn't answer your question, but my guess is that you could use substitute them for black pepper in any recipe...or, if you want a recipe that foregrounds their flavor, maybe consult an Indian cookbook.
"Don't you ever underestimate the power of a female." Bootsy Collins