There are a few online places. First I would start wtih https://ctftime.org/
, look at the upcoming CTFs.
Next I would check your area for the local CitySec or Defcon groups, maybe 2600. You might need to travel a little way, 2600 and the best CitySec in my opinion are just over an hour away from where I work and live.
Look around the local colleges near you, see if any have an Information Assurance or Cybersecurity program, and find out if they have a club. Ask to come to a couple of club meetings, under the pretense of thinking about joining the program. Ask if they have a PvP hacking night (some are limited to their competition team members) or see if they want to do some CTF stuff with you.
Can always start a group, find people in your area via twitter that are interested in InfoSec and see if they are meeting or would be interested in getting coffee as a group. Get established see if anyone wants to do a CTF or weekend attack defend lan party.