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We have carried out a sensitive search for gas emission lines at IR and millimeter wavelengths for a sample of 15 young Sun-like stars selected from our dust disk survey with Spitzer. We have used mid-IR lines to trace the warm (300Y100 K) gas in the inner disk and millimeter transitions of 12CO to probe the cold (20 K) outer disk. We report no gas line detections from our sample. Line flux upper limits are first converted to warm and cold gas mass limits using simple approximations allowing a direct comparison with values from the literature. We also present results from more sophisticated models following Gorti & Hollenbach that confirm and extend our simple analysis. These models show that the [S i] 25.23 m line can set constraining limits on the gas surface density at the disk inner radius and traces disk regions up to a fewAU.We find that none of the 15 systems havemore than 0.04MJ of gas within a few AU from the disk inner radius for disk radii from 1 to40 AU. These gas mass upper limits even in the eight systems younger than 30 Myr suggest that most of the gas is dispersed early. The gas mass upper limits in the 10Y40 A