Hi Kai,
Attaching a camera to your microscope can be tricky and expensive. There are a few "cheapies" like the motic 352 eyepiece camera, but it still costs more than $200 (you might google search eyepiece camera or look for low cost telescope cameras). When I worked in the biology department, we created a tube that attached a sony camera to the eyepiece of a stereomicroscope. You set the camera for macro mode, focused through the tube on the eyepiece, and had a fairly cheap method of photographing through the eyepiece. You might also get an eyeclops from the toy store and see if it can work as a sort of capture device.