Normally Garter Snakes settle well into a captive environment, Lindsey. For general information on their needs try reading through this article;
http://www.thamnophis.com/caresheets...ake_Care_Sheet
But, just to point out, most of the snakes in your pictures are not Garter Snakes, but are Brown Snakes (or Dekays Snakes)
Storeria dekayi.