Beginner: Shy away from "900x Power!" Department store brands (These are OK but have alot of plastic on it and a wobbly mount or focuser). I suggest a scope such as a 6-8" Dobsonian Orion SkyQuest for this. These are in the 300-400$ range. But you can also get good quality entry level scopes from Meade and Celestron. Accesories I suggest for this is a Lunar filter or, if you want to, a filter set, ranging from 45-120$ or so.
Intermediate: For someone who knows enough about stars and planet to point out a few constellations in the sky, or if you just want to see more of the celestial wonders, you may want to consider an Equitorial mount. This is not as easy as an Alt-Azimuth or dobsonian but here are some tips about them that I have found useful:
1. Try to balance the scope before every observing session. To do this, unlock the 2 knobs for Right Ascension and Declination, move the scope into various positions to see if the movement stops and dosen't just glide. If out of balence, move the counterweight up or down on its shaft WITHOUT taking off safety cap off the end of the counterweight (I don't want to be responsible for any broken toes or fingers.) Repeat this step until the scope stops shortly after you let go of it.
2. You might want to try to get a clock drive on the mount, which is a small set of motors to keep an object centered in the eyepiece. You can also make small adjustments by directing which way the motors should go with a hand controller
Advanced: When you really know your way around the sky and know concepts of nebulas, star life cycle, etc., you are ready for the "Big Boys" It does however, start to get expensive. A Schmidt-Cassegrain such as the LX200s are very popular and are great scopes. But you still have to be careful what you buy. Reasearch the product and make sure you really want it before you purchase it. You can also ask the opinion of other astronomers that you know or ask astronomers at forums like www.njnightsky.com for opinions.
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