Here’s what I’d do…
1) Find any message boards, online forums, social media groups, blogs, etc…that have to do with a promoter or group of folks locally who are into stuff that you’re into.
2) Join them and just chat. Don’t go in immediately saying you’re a DJ looking for gigs and then you start spamming your mixes on them. No one will listen and some will tear into you to the point you leave in frustration. The goal isn’t to promote but to gain the favor of these people. Chat, communicate, act like you’re just a patron.
3) After a bit, post a mix, ask for opinions. Let them chime in.
4) Go to the events this promoter throws. Be a patron…since many promoters frown on the DJs who never come to their events except when they think it’s a chance to spin.
5) If you get to know the promoter even more, try to see if you can get into their inner circle. Help them promote, be a part of them. If you’re at least “in good” with them, give a demo and ask them what they think.
That’s what networking is. Gaining acceptance from groups so they trust you to play music for them.