Many Kosher products are available in local supermarkets (HEB, Randalls, Kroger, Trader Joes, Whole Foods).

Some have small Kosher sections in the ethnic food aisle. They typically carry, grape-juice, bamba, chocolate, yartzeit candles etc.

Locally, the largest selection and best-quality Kosher chicken, beef and lamb, are available at Chabad of The Woodlands (items are frozen). Click /media/pdf/1039/kGqH10390200.pdf here to see what's available.

Trader Joes on the corner of Woodlands Pkwy and Gosling carries a limited selection of fresh Kosher meat and chicken under the Teva and Empire brands. Whole and cut-up chicken, brisket, ground beef, stew meat and rib-eye.

Specs carries Kosher wine.

There is also a Facebook page that updates local Kosher options. 

However, the widest range of Kosher products will be found in the Houston supermarkets