The standard solution is to use two (or sometimes four) lights set at about 45 degree angles to the surface you are copying, and at a distance great enough that (a) there isn't a huge degree of falloff or an obvious bright spot from either light; and (b) that the angle of the light at the surface closest to the light is not so high that you get direct reflection off of the paper into the camera. Something like this:

Since you are working with books and periodicals, you'll probably find that lighting from the top and bottom of the page, rather than the sides, will provide the fewest deleterious shadows, and that will likely mean shooting from the side of the page. The best orientation for shooting will probably not be the best orientation for reading. You may find that you get most even lighting using a pair of linear-tube fluorescent lamps or "banker" style long-filament incandescent bulbs. (If you are working with very glossy and textured originals, which is likely not the case here, then using polarizing gels on the lights and a polarizing filter in the opposite orientation on the lens will eliminate glare at the cost of significantly longer exposures.)

As for getting the overall exposure right, it depends what exposure controls the camera provides. If you only have automatic exposure at your disposal, there may not be much you can do (apart from post processing) to fix things when the page doesn't meet your camera's expectations. You can try alternate "modes" on problem pages to see if that helps, since "text mode" will be working with some assumptions about how much of the page is covered with ink (typically 15% or so), and if the page is much different from what the camera is expecting (such as having much higher than normal ink coverage due to illustrations, etc.) you will get either overexposure or underexposure. (If you have manual control or some means of accessing exposure compensation, then you should have no problem.)