Go to
www.uspsa.org and use the "club-finder" function. Find and go to a club match in your area. Observe and ask questions. You will be helped.
Then come back here and ask more questions, because we WANT YOU to join us in the fraternity of shooters.
It is so much fun..............
Cost? Less than you think, but more than you want. Seriously, if you already have a centerfire handgun of 9mm or larger then you really don't need much more.
Do what I suggested: go. Ask. Try. Enjoy.
See, old, but still havin' fun.