1) Both Astronomy Magazine and Sky & Telescope have excellent articles on how to buy a telescope on their web sites. I strongly encourage you to read both before you do anything else.
Astronomy How to buy a telescope
S&T How to buy a telescope here.
2) You don't say in your profile where you are, but most reasonable size towns/cities have an astronomy club of some kind.
FIND THE ONE NEAREST YOU AND GO TO A STAR GAZE. This is not an option. You will find the people will be more than eager for you to look through and play with their scopes. They will tell you all of the things they like and all the things they don't like. This will allow you to decide what you like and don't so you can get the correct scope for you.
3) While you are at #2, you will almost always find someone selling a scope. If the one you want isn't available right away, just be patient, it will be.
4) The thing to remember with telescopes is that, aperture is everything. If you have the choice between a 3" ETX and 6" dob, the dob will amost certainly give you the better image.
Good luck and remember! When you buy something, you have to come back here and tell us all about it.
