As I'm somewhat fond of saying, it is partly (and a big part, at that) the music that makes a Goth, well, Goth. I have also said that it's quite important to have a good knowledge and understanding of early, 'traditional' Goth music (e.g. the Banshees, the Sisters, etc.). And on top of that you may like to have a good working knowledge of modern genres of Goth music too, at the very least to avoid feeling a little out of your depth at your local Goth club. But one thing that I'm not sure I've pointed out is that you don't actually have to LIKE any one particular band to be a Goth.
But please, please, don't ever think that if you're not totally enamoured with, for example, Bauhaus, you can't ever be a 'real Goth'. There are many, many, many genres of Goth music, and presumably, if you've been interested in Goth for a while, you'll know of at least one Goth band that you like. That is your starting point. Ask people on forums to recommend you similar bands. Use Last.fm or the recommendations tool on Amazon. Go to Goth clubs, and when you hear a song that you like, ask who it's by.
(Haven't yet heard any Goth bands that take your fancy? There's a big ol' list in the sidebar to the right. Get Googling, my friend.)
Hey, to get you started, I'll give you a link to another awesome free download (click the song title below, and never say I'm not good to you). It's from a brilliant band called Rising Shadows, who are classified as ethereal, neofolk, medieval and darkwave, to name but a few genres (I'm pretty sure I've mentioned before that the world of dark music gets just a leetle bit confusing...). The title of the song is Fate of Us All, and I have to say I think it's utterly beautiful.
Now, what was I saying? Ah, yes.
You may have a very good idea of what Goth bands you DON'T like. For example, I am not the world's biggest fan of Joy Division (although Love Will Tear Us Apart seems to be growing on me). And yes, there will be the snobby elitist people who will make out that, if you don't like The Sisters, you are not A Proper Goth. Well, don't listen to them. As long as you like SOME Goth music, how exactly are you not a Goth?
Just to prove my point, I pulled these quotes from a discussion on Goth.net about overrated bands:
"You know who I have trouble getting into, outside of a few songs? Fields of the Nephilim. They seem like a band that I should really like, but I can't often listen to Dawnrazor from start to finish and the only time I watched the "Moonchild" video it seemed like it couldn't end quick enough."
"Einsturzende Neubauten. I simply cannot get into their stuff at all and I really can't understand why everyone in the goth scene raves about them so much. I probably sound like an old codger for saying this but...to me it's just noise."
"I don't enjoy classic goth rock like Bauhaus and Joy Division, but I appreciate it and its significance. I myself just like a more modern sound."
"The Cruxshadows. They've been extremely popular for awhile now, and I really can't understand what's so utterly remarkable about them."
Listening to: Misery Loves Company - Emilie Autumn