The Collaborative International Dictionary of English v.0.48:

Guttersnipe \Gut"ter*snipe"\, n. (Slang)
   1.
      (a) A small poster, suitable for a curbstone.
      (b) A curbstone broker. [U. S.]
          [Webster 1913 Suppl.]

   2. same as street Arab.
      [PJC]

   3. a person of low moral character.
      [PJC]

WordNet (r) 3.0 (2006):

guttersnipe
    n 1: a child who spends most of his time in the streets
         especially in slum areas [syn: street urchin,
         guttersnipe]

Moby Thesaurus II by Grady Ward, 1.0:

74 Moby Thesaurus words for "guttersnipe":
   Arab, Babbitt, Philistine, arriviste, beach bum, beachcomber,
   beggar, bo, boor, bounder, bourgeois, brat, bum, bummer, cad,
   churl, clown, dogie, epicier, gamin, gamine, groundling, hobo,
   homeless waif, hooligan, idler, ill-bred fellow, landloper,
   lazzarone, loafer, looby, losel, lout, low fellow, mucker, mudlark,
   nouveau riche, parvenu, peasant, piker, ragamuffin, ragman,
   ragpicker, ribald, rogue, rough, roughneck, rounder, rowdy,
   ruffian, ski bum, stiff, stray, street Arab, street urchin,
   sundowner, surf bum, swagman, swagsman, tatterdemalion, tennis bum,
   tramp, turnpiker, upstart, urchin, vag, vagabond, vagrant,
   vulgarian, vulgarist, waif, waifs and strays, wastrel, yokel