I just found this link this morning: If you’d like to access a lot of Church publications in PDF format, click here.
You’ll find magazines, such as the Ensign and Friend, Sunday School (for example, Old Testament Times at a Glance) and youth materials (such as the Young Women Camp Manual), all nine volumes of Teachings of the Presidents of the Church (here is the David O. McKay manual, for instance) even the Bible and the Triple Combination.
Have fun with these links.