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We report Giant Metrewave Radio Telescope (GMRT) 21cm observations of twoconfirmed and one candidate low redshift damped Lyman-alpha systems (DLAS). HIabsorption was detected in the two confirmed systems, at z=0.2378 and z=0.5247,with spin temperatures (Ts) of 2050 +- 200 K and 330 +- 70 K respectively. Thenon-detection of absorption in the third (candidate) system places an upperlimit on its optical depth, which in turn implies a 3sigma lower limit of 850 Kon its spin temperature. Ground based K-band imaging observations (Turnshek etal. 2000) have identified the low Ts absorber with a spiral galaxy while thehigh Ts system appears to be an LSB galaxy. This continues the trend notedearlier by Chengalur and Kanekar (2000) of low spin temperatures for DLASassociated with spiral galaxies and high spin temperatures for those with nosuch association.  Combining these new results with 21cm observations from the publishedliterature, we find that (1)The 21 cm equivalent width (EW21) of DLAS increaseswith increasing column density (NHI). Further, absorbers associated with spiralgalaxies have systematically higher EW21 at the same NHI than DLAS with no suchassociation, (2)DLAS at high redshift (z > 2) have small velocity spreads(DeltaV), while, at low redshift (z < 2), both large and small DeltaV areobserved. These trends are in qualitative agreement with hierarchical models ofgalaxy formation.Comment: (8pages, 7 figures, accepted for publication in A&A

HI 21 cm absorption in low $\vec z$ damped Lyman-αsystems