When are usually the applications deadlines in United States for a Computer Sciences graduate program?
There are official dates, set by each program.  Most of those are in the winter prior to the autumn in which you hope to start.  Of the timelines and deadlines I'm aware of, it's too late to apply for starting fall 2016 at most schools. Especially if you haven't yet taken the TOEFL and GRE, you should be targeting next year's cycle (assuming you still want to apply then).  It takes a while to get those tests scheduled, taken, and graded, and you generally have to have scores in by the application deadline. 

A quick survey of Masters' application deadlines for schools in the first page of Google results: 


Stanford: Dec-08
Columbia: Feb-15 (but may accept some late)
Chicago: Feb-01 for international students
Brown: Mar-15
Carnegie Mellon: Dec-15 
Georgia Tech: Feb-01
UT Austin: Dec-01
Illinois: Dec-15
Michigan: Jan-15


Look for programs that are of interest to you and then check their application deadlines for a specific answer.