Some of the same Hollywood stars who were in Washington three weeks ago for the premiere of "Samaritan: The Mitch Snyder Story" will be holding a press conference in California tomorrow to express their support for Snyder's latest hunger strike. He goes into this strike even against the advice of members of his organization, the Community for Creative Non-Violence, who argued the White House may not respond to the tactic this time.

At the press conference, actors Valerie Harper and Dennis Weaver, cofounders of LIFE (Love Is Feeding Everyone) will ask people across the country to call or cable President Reagan to release the $5 million promised to rehabilitate the 1,000-bed shelter for the homeless at Second and D streets NW. Other stars expected at the press conference include Linda Gray of "Dallas," Michael Warren and Barbara Bosson of "Hill Street Blues," Cathryn Damon of "Webster," Miss America of 1983 Debbie Maffett, producer Stephen J. Cannell and actors Ned Beatty, Mike Farrell and Shelley Fabares.

The Mystery Free Agent

It was a bit tense yesterday at the office of Baseball Commissioner Peter Ueberroth. After the California Angels had made the next-to-last selection in the Amateur Free Agent Draft, a spokesman in Ueberroth's office announced a special selection had been granted to the New York Yankees and that they picked G. Frederick Will, an infielder out of Champaign, Ill.

The Toronto Blue Jays, who held the last pick, were livid and demanded an explanation, as did Seattle, Detroit, Cincinnati and the Chicago Cubs, California and Los Angeles. It was just an Ueberroth joke. The draftee was George Will, columnist and baseball fan who once played second base for the Little League Mittendorf Funeral Home Panthers in Champaign, where he grew up. Will had no explanation for the joke but said of Ueberroth, "I suppose he knew that it would be the highlight of my life. It's all downhill from here."

End Notes

Michigan Rep. Bob Davis, 53, is in serious condition in Fairfax Hospital recovering from a mild heart attack. He was taken to the hospital shortly before he was to give a commencement address Saturday at Congressional Schools in Falls Church. His wife Marty Davis said yesterday that Davis was not feeling well when he returned from jogging earlier that day but decided to keep his scheduled speaking engagement. Davis is expected to remain in the hospital another 10 days and recover at home for a few weeks . . .

Also on the mend is former actor-producer John Derek, 59, the man who has been married to some of Hollywood's most celebrated beauties. Derek was taken to Cottage Hospital in Santa Barbara, Calif., Sunday night by his wife Bo Derek after suffering a heart attack at their horse ranch outside town. The heart attack was described as "mild" and a spokesman said no surgery is planned right now. He will remain in the hospital under observation for a time. Derek was previously married to actresses Patti Behrs, Ursula Andress and Linda Evans . . .

The hilltop house north of Beverly Hills where the late actor Rock Hudson lived for 20 years is up for sale. The home in which he died in October, in the area of Los Angeles known as Beverly Crest, is a Mediterranean-style mansion with a 20-car courtyard, private theater, pool and tropical forest. The asking price is $2.95 million . . .

*Having considered the constant complaining about the availability of available men in Washington, the National Capital Area Chapter of the March of Dimes has decided to raise money through a "Bachelor Bid." The idea is that 20 of Washington's "most eligible and sought-after bachelors" and date packages will be auctioned off to the highest bidder June 20 at International Square. Among the hot properties going on sale are Steve Varsano, once a Cosmopolitan magazine "Man of the Month"; Chris Jagger of WRQX radio; Fairfax Hackley, fitness consultant; Rick Swartz, WJLA-TV; Duke Zeibert of restaurant fame; and Kenny Jenkins and Monte Coleman of the Redskins . . .

Herb's Restaurant, a one-time popular artist's bar on P Street that has been closed for about a year, is coming back in a new location. Herb White and Aaron Levine have purchased a building on 14th Street NW near R Street for a new Herb's Restaurant. White said the new location will include a performance area, an art gallery and a meeting place in addition to restaurant and catering facilities. He didn't say when the restaurant would open . . .