This link gives some general information, but has additional links that should be useful.
http://www.redraiders.org/at/3d.pdf
Our club allows individuals to shoot and score. Scoring is 12,10,8, 5 and 0. In the shoot yesterday, it was a "bonus" shoot, with 4 targets at marked yardages with higher values for scoring areas. A good shot on a 60 yard target could help bring you back if you're scoring low on the short shots!
Lyle