My goal in this instructable is to provide a set of resources for anyone interested in getting started with this hobby, in the form of a step by step guide for someone who just isn't sure where to begin. When I got started a few years ago, I couldn't find any guides like this that really made sense to me, so in a way this is written to my past self. If I had this guide, I could have avoided a lot of trouble, pitfalls, useless purchases, and dead ends. Furthermore, I've been interested in astronomy since I was little, but I always assumed it was an expensive hobby that I couldn't afford to get into--I was wrong, and I wish someone had been there to tell me!
If you can think of anything I should add to this guide, make sure to leave a comment below--if I use your suggestion, I'll send you a DIY patch. If I think it's a big enough suggestion or oversight on my part, I'll also send you a coupon for a three month pro membership. Also, as I live in the northern hemisphere and only see the northern sky, if you're reading this from a southern hemisphere perspective, I encourage you to write a supplementary southern hemisphere version of this instructable. If it's up to my standards (as determined solely by me and my whims) I will link to it here and send you a coupon for a one year pro membership! I envy you, too, I'll probably never get to see the Magellanic Clouds.
Finally, please lend me your vote in the Space Contest. If you found this useful or interesting, cast a vote my way!
Step 1: Don't Buy a Telescope!
People who have been doing this for a while have a name for those telescopes--they call them hobby killers. Those things are incredibly difficult and frustrating to use, and aren't good for much except looking at the moon, and while that's definitely worth doing, don't take that step yet. The one I bought was awful, I used it a couple of times and then put it away, convinced I was doing something wrong. It put at least a two year break between me deciding I wanted to get into astronomy and me actually doing so.
You will probably want to get a telescope some day, but you really don't need one yet, and you most definitely don't know what kind you want. There is a wealth of options out there, and you should take some time to learn about them before you settle on one to buy (more on that in a later step).
If you absolutely must spend some money on something (I know sometimes if I drop a few bucks on a new hobby I feel obliged to see it through), buy a Planisphere. This is a very useful resource you will come back to over and over again, and worth the few dollars it will cost.
****Update 8/1 -- dimtick has pointed out that another good, small investment is a green laser pointer. They are very cheap these days, and if you're planning on involving anyone else in your hobby they are great for pointing out what you're looking at. Also, they're fun!