Hi Tim,
If the grocery stores in my town have the vegatables labled correctly (the cashiers never know), it is a plant that looks similar to celery only the stalks are white and much wider and flatter. Instead of fine leaves, it has thick dark green leafs at the end of the stalks with white veins extending from the stalk portion into the leafy area. The bunches are usually much thicker than celery and some what shorter.

I prepare by washing and cutting off the bottom edge of the stalks. I then cut into 1/4" stripps crossways from bottom to top. After I heat a little oil (or bacon fat- pork fat rules!) in a frying pan, I add the white stem parts. I stir fry this at highish heat for a few minutes the add the green portion. for long enough to wilt it. I love this as a side dish with my morning omlet or with baked fish.

John this might even qualify as a recipe,
(please feel free to edit)
Ike