I'm new and I have some questions...

Hi I just joined and I had a couple of questions, are there actual stores I can go to that have supplies for spells and what not? (I live in Los Angeles) Also once Ive cast a circle what do I do next? Like what's the purpose of casting one? And do you know of any simple spells I can' try out? 
Also I was looking on here and I saw people talking about faeries so I was wondering can you actually see them?