All calculus students need to know and understand unit circle trigonometry, which includes know radians, the relationship between the unit circle and the sine and cosine functions, knowing tangent, cotangent, secant, cosecant, and the inverse trig functions: Arcsine, Arccosine etc. You need to know the value of the sum of the sqares of sine and cosine, the law of cosines, the double angle formulas, the formulas for cos(a+b), sin(a+b) and should have seen the proofs of all these identities.
The best way to review this for your calculus courses, is to read the textbook you learned this material from and to practice problems. The textbook used at Lehman College is Cohen's Precalculus with Unit Circle Trigonometry. Keep in mind that it is possible that the class you took might not have covered all the necessary material or that you may not have learned all of it correctly. Be sure to review all the topics mentioned above and do practice problems. Tutorring is availble at the MATH LAB.
There are also free online tutorials for trigonometry:
The math page has a quick review of trigonometry. All Calculus students should know sections 16-19. However, this website doesn't go far enough.
Dave's Short Course on Trigonomery sections 11-16 covers everything a calculus student should know.
Spark Notes SAT II Math IIC has a quick review of the necessary trigonometry for calculus students ending with a list of review questions that have been worked out.