How do you split one hydraulic outlet on a tractor into two cheaply?

You put a manual selector valve in between you spool valve and your outlet,turn handle to chose ,costs about $60.

Nothing hydraulic is cheap; however, if you buy a double hydraulic control and appropriate hoses, that is the cheapest way to go.

You can get a T-piece and fit it into your existing outlet line. Just be sure you have enough flow for the implement you are using. The only problem is that a t-peice will not allow individual control of either outlet, so you need 2 controls to contol each independently.