To get started you really need to shoot with someone that knows about trad gear. Don't take a chance on buying a garage sale bow right now. Old bows can have unseen cracks and twisted limbs. I suggest going to one of the Tannehill shoots that BhamFred mentioned. Most of the trad guys will be more than helpful to a new guy at one of those shoots. You won't meet nicer folks.
The size and poundage depends on you and your strength. I prefer a 60" longbow for shooting and hunting. I use a 47# bow and have used it to shoot deer out to 25 yds. I use razor sharp Simmons broadheads. Deer and hogs can not handle a Simmons broadhead.
Where to shoot different bows? Tannehill shoot.
The range depends on the sharpness of your broadhead, the weight of your arrow, and how much you practice.
I began shooting trad bows because of my cousin. He is hands down the best shot and best hunter I have ever had the pleasure to hunt with. If you ever log in to Georgia Outdoor News Forum and look at the Trad Bow forum he goes by the handle RC. He taught me and challenged be to be proficient with this equipment. Once you've shot for a while range finders and distance becomes obsolete. It's like throwing a baseball or football. You don't QB's using range finders. It becomes hand-eye coordination and anchoring at the same spot. Now, there are those who still want to aim using the arrow's tip or by gap shooting. I forced myself to shoot by simply looking at the target and concentrating on a small spot and releasing. Finally, it all came together. Even now I can take my bow out, take a few warm up shots and then be ready to hunt. Don't get frustrated! There is a learning curve. Shoot, shoot, shoot, shoot and shoot. Shoot at little targets, big targets, animal shaped targets, square targets or just anything that can take an arrow. Shoot at various distances. Finally, HAVE FUN. I have killed deer that I could have never killed by looking through a peep site. Late evening or early morning shots become easy because low light doesn't effect your aim. I've shot hogs at night only using bright moonlight. I hope you enjoy it Clem.