Here ya go Jeff.
The stamp replaced the Striped bass stamp in 2004.
It will be required to fish any of the Delta region events.

1.18. Bay-Delta Sport Fishing Enhancement Stamp

A person shall not sport fish in the tidal waters of San Francisco and San Pablo bays east of the Golden Gate Bridge and west of the Carquinez Bridge, (i.e., all tidal waters, sloughs, canals and forebays within the area east of Highway 101, west of Highway 29, west of Interstates 80 and 880, and north of Highway 237, including the Napa River below the Trancas bridge in Napa, Sonoma Creek below the Highway 121 bridge and the Petaluma River east of Highway 101), the Carquinez Strait, the Sacramento-San Joaquin Delta (i.e., all rivers, sloughs, canals, cuts, forebays, and flooded islands within the area south of Interstate 80, west of Highway 99, north of Interstates 580, and 205, and Highway 120, and east of Interstate 680), the Sacramento River below Keswick Dam, the Feather River below Oroville Dam, the Yuba River below Englebright Dam, the American River below Nimbus Dam, the Cosumnes River west of Highway 99, the Mokelumne River below Camanche Dam, the Calaveras River below New Hogan Dam, the San Joaquin River below Mendota Dam, the Stanislaus River below Goodwin Dam, the Tuolumne River below La Grange Dam, and the Merced River below Crocker-Huffman Dam, unless he or she first obtains, in addition to a valid California sport fishing license and any applicable stamp issued pursuant to Section 7149 or 7149.05, a Bay-Delta Sport Fishing Enhancement Stamp and affixes that stamp to his or her valid sport fishing license. 2004 Freshwater Fishing Regulations can be found online at: http://www.fgc.ca.gov/2004/freshfishregbook04.pdf or pick up the booklet where you buy your fishing license.