A small cultural label such as Discos Pentagrama — which records unknown regional folk groups around Mexico and Cuba — would never get much shelf space in the big chain music stores, but at Down Home Music in El Cerrito, it gets equal billing. Started by Chris Strachwitz in 1976 and managed by John McCord, Down Home Music stocks around 24,000 roots and world titles. During a recent visit, we found rare CD pressings by pioneers like Mariachi Coculense from Jalisco and legendary Yucatan troubadour Guty Cardenas. Folk music rules at Down Home, which also carries box sets of Veracruz sones, albums of marimbas in Chiapas, fiddle tunes from the Gulf Coast huasteca regions, brass band bandas from the Pacific, and the infamous accordion-fueled narcocorridos from Northern Mexico.