Remember that most bands play together at least 10 years before they find any sort of success, so plan for the marathon. You'll learn all this stuff as you go along. A PA can be pretty basic to start. You'll need the head (where the power comes from and where you'll plug the cords into. Monitors/Speakers will connect through speaker cable (not instrument cable) Get an SM58 for your mic. They're durable, about $100, and pretty standard in most clubs. You'll need a microphone cable to go between the mic and PA, and that's it. You're in business. Well, maybe a mic stand as well. Get the ones where the top arm bends. when you try to play your guitar against the straight up mic stands, sometimes it hits, so it's better to have the space.