Buy (or borrow):
Theory of Wing Sections
by Abbot and von Doenhoff.
It has CL and CD vs AoA graphs for many aerofoils, including the NACA 2412 used in the C172 (IIRC). You could fit curves to the data.
It also includes some simple corrections, eg:
For the 2D-3D correction, CL_finite_wing = A/(A+2) x CL_wind_tunnel
where A is the aspect ratio.
It also has some "challenging" maths, if you are up to it.
Happy reading!