The rule of thumb you usually hear is "1-2-3." That's one week in primary, to complete the fermentation. Two weeks in secondary, where you may move the beer to a second container, if you wish (many don't, though). And three weeks in the bottle before the amber liquid starts to reach its potential.
Me, I bottle after three weeks in the original fermenter. That makes the next three weeks really hard to take, since all you have to do is pop a botle in the fridge. On the other hand, it's a great way to observe the conditioning as it happens.