Tried this a few years ago betweeen rows in the vegetable garden, four sheets of newspaper covered with about three inches of grass. It does work reasonably well but, wet or dry, you have to be extremely careful walking because it becomes very slippery. Never tried it again and now shred (by hand) newspapers and add them to the compost pile.
I do this all the time however I apply a layer of hardwood mulch over the top. It has been wonderful in preventing weed growth and is easy to place around the existing plants. It seems that where it has been used the earthworms are the most happy...I suggest this as a practice. I have never used newspaper alone or with any other type of mulch other than hardwood.
I do the same as phw, always put mulch on top and have had great success at keeping the weeds at bay. By the next spring the newspaper has really broken down and only bits of it can be found. I love newspaper as a mulch base!