While I know there are classes, I don't know of one in your area.
A lot of people get along without them.
Some ranges require an introductory lecture or class, a few even require you to demonstrate your ability. But not many. ASK!
Random videos of Joe Blow running and gunning may not be helpful.
The New Shooter Information and New Shooter Briefing at:
http://www.gadpa.com/index.php/idpa/new-shooter-information/
http://www.gadpa.com/index.php/idpa/new-shooter-briefing/
are helpful and may be enough to get you going. They are clearer than the current rule book and have the basics.
To be "ready" all you
have to do is be safe and be able to follow CoF (Course of Fire) instructions.
To get through that CoF...
You must be able to operate your gun mechanically and fire it with some hope of hitting a target.
You must be able to draw it from under concealment without getting tangled up. (Some places waive concealment for new shooters.)
You must be able to shoot safely while standing, sitting, walking, peering around cover, kneeling behind low cover, and prone under very low cover.
You must be able to move between firing points briskly with gun in hand but finger out of trigger guard.
You must be able to reload, usually behind cover, without waving the gun around.
Note that everything except actual marksmanship can be practiced dryfire at home. Your family will think you strange for kneeling behind the easy chair snapping in at the bad guys on tv, but it is good practice.
I have the Four Priorities:
Safety: Don't hurt anybody, don't scare anybody, don't get disqualified for safety rule violation.
Execution: Pay attention and follow the CoF. Don't get procedural penalties for doing stuff wrong.
Accuracy: Hit the target. Hit the target in the middle (or head). Learn to call your shots so you are not peering at the target to see if you hit it.
Speed: Move along, your time is your score. But don't rush it to start with, walk before you run, LITERALLY. Just know what you are doing and don't dawdle around.
You can do all that and still have fun.