Yeah, those figures look hand made or the work of a plotter from years ago and THEN scanned in.
For the sinusoidal plot, there are quite a few programs you can use to draw that...Octave, Matplotlib, Maxima, Latex, Asymptote and the list goes on...probably the easiest for you to use is Excel.
For the other figure any just about anything will do...Inkscape, Gimp, MS-Paint...