Edmund's device is made of cardboard, but is nonetheless fairly rugged. David Chandler's The Night Sky planisphere reduces distortion by splitting the sky into two maps. The two-sided planisphere succeeds in reducing distortion, and it's easy to use once you get accustomed to it. Magazines are excellent investments. Many come with a monthly star chart, and all contain useful sky information.
Material ranges from introductory level to advanced.
Available from Sky Publishing Corporation. Astronomy magazine is considered by many to be an excellent introductory publication. Astronomy features lots of artwork, and much of the text is written in an informal, enthusiastic style. Available from Kalmbach Publishing Company. Bear in mind that the most expensive star map is not necessarily the best for the beginning observer.