To be honest, one of the most important skill someone can have as far as training goes is knowing when to add weight. You can't always have a chart tell you which weight to use or someone to tell you when to add weight, you need to find that out for yourself.
With "bodybuilding" work you have to understand that you CAN make an easy weight tougher and it will be effective, but you can't make a weight that is too heavy work, because too heavy leads to improper form and muscle compensation (less tension on the target muscle).
So with bodybuilding work it's better to progress more slowly. Add weight when you can no longer make the set demanding with a certain weight.