Seems like you've been teased into audio. Like Michael said, it can get expensive, ridiculously so. Digital for instance has been steadily advancing for 30+ years, so avoid overspending. Now a days its all about downloads, so don't buy spinners of any kind, instead use computers with plenty of storage. Avoid large discount stores as their gear is over specified, offer little service, and even less decent advice. Hang around here to get a good start.
Your first step should be to get a suitable room (larger, NOT a square) that ideally can be setup as a dedicated listening room. Then shop for speakers, which implies knowing what you want, auditioning, and taking notes. Knowing what you want means educating yourself on pros and cons of different designs/brands and how they fit into that suitable room. Auditions should include listening at home. Note taking forces you to really listen and protects from fleeting aural memory.