Sorry, forgot the /sarcasm.....my paper is full of sh_it.
The rule of thumb, according to one of the local county ag agents, is to stay away from glossy paper & highly colored paper when using newspaper as mulch. We usually just stick to the newspaper itself, not the ads, when we've used newspaper as mulch. Grass clippings will also work as mulch, but make sure of the source. A lawn that's been treated for weeds will have traces of weedkiller in the clippings and will kill vegetable plants and flowers.
Currently, we use black plastic as a cover, weight it down, poke slits in it and plant the plants.