Where can I find thousands of actual images of stars in the galaxy?
The online version of the digitised sky survey will give you as many images of the sky as you want. Be aware that these are based on photographic plates. Also be aware that every imaging system has its own peculiarities in terms of the shape of the point spread function (i.e. the shape of a star in the image) and features such as diffraction spikes.
https://archive.eso.org/dss/dss