Sam and Max Season 1 is $26.95 US on Steam. That's about $25.20 Canadian. Absolutely no tax is charged for us. It's all 6 episodes. I've heard some GREAT things about this series and it's a pretty darn cheap. 50% off the full price if you bought them individually.
http://www.steampowered.com/v/index.php?area=package&SubId=539&cc=US
http://www.steampowered.com/v/index.php?area=package&SubId=539&cc=US