I will admit that in my early Goth years my biggest idol and inspiration was Amy Lee of Evanescence, whilst I still love Amy Lee and have a poster of her on my wall I have branched out a little bit over the years!
When I was first getting into Goth I used to endlessly watch those Goth picture slideshows that you can find millions of on YouTube. I love a lot of very stereotypical 'spooky' imagery - lonely woodlands, graveyards, desolate houses, thunderstorms etc. Often the world itself provides inspiration; when I get writer's block I flick through a bunch of landscape photography books that I keep to hand.
The list of people I find generally inspiring is a long one; for general attitude I'd have to cite Gerard Way, Joji Grey and Jillian Venters.