  We present the first results of a targeted survey carried out with the 305 m
Arecibo telescope to detect HI-line emission from galaxies at redshift z>0.16.
The targets, selected from the Sloan Digital Sky Survey database, are
non-interacting disk galaxies in relatively isolated fields. We present here
the HI spectra and derived HI parameters for ten objects detected in this pilot
program. All are massive disk galaxies in the redshift interval 0.17-0.25 (i.e.
2-3 Gyr look-back time), with HI masses M_HI=3-8 x 10^10 Msun and high gas mass
fractions (HI - to - stellar mass ratios ~10-30%). Our results demonstrate the
efficacy of exploiting Arecibo's large collecting area to measure the HI mass
and rotational velocity of galaxies above redshift z=0.2. In particular, this
sample includes the highest redshift detections of HI emission from individual
galaxies made to date. Extension of this pilot program will allow us to study
the HI properties of field galaxies at cosmological distances, thus
complementing ongoing radio synthesis observations of cluster samples at z~0.2.
