Just make the image in greyscale as if you would see it through your eyelids (blurry).
Then use convert grayscale->bitmap with halftoning on to convert it to a black and white bitmap.
With this function:
-The dots are very realistic to real halftones, instead of the halftone function which always produces circles (and halftones are square at de 50% grey point)
-The black and white image can be imported in your vector image program, and can be given any PS front and back colour. Much easier way to incorporate it into your total artwork.