Your best bet for a spot start tomorrow if you're in a shallow league is Tommy Hanson (owned in 62.7 percent of ESPN leagues and 65 percent of Yahoo leagues). The immensely talented rookie has been mediocre as of late (yielding 13 runs over his last 25 IP); however, he faces the league's worst offense (San Diego) tomorrow...in the league's most pitcher-friendly venue (Petco Park). Furthermore, Hanson owns a 2.64 ERA on the road...more than a point better than at home.
For those in deep leagues who are desperate for innings, you could consider Doug Davis. Admittedly, Davis' 1.50 WHIP indicates that his 3.73 ERA is misleading, and he's given up 15 runs over his last four starts spanning 18.1 IP. However, tomorrow he faces Pittsburgh's 25th-ranked offense at PNC Park.