"What power supply do i need to power 60 1.5v dc motors that draw about 200ma?"
So, I'll make this simple. If the motors are paralleled with the supply then the current adds, if they are in series the the voltage adds together. 

If I have 1.5V motor that draws 200mA, I need a 1.5V power supply that can output at least 200mA, I could use a 400mA supply and the motor would still draw 200mA (assuming the power supply is regulated). You can also calculate the power P=I*V, power= current * voltage, 0.3watts = 0.200 Amps (or 200mA) * 1.5V

If I have two 1.5V motors that each draw 200mA there are two configurations I could put them in. I could put them in series or in parallel. In series I need a 3V supply, and each motor will still draw the 200mA it needs. In parallel I need a twice the current. I can still use a 1.5V supply, but I need 400mA of current.







simulate this circuit &ndash; Schematic created using CircuitLab

If you have 6 motors in series, you need a 1.5V*6(motors) = 9V supply that will draw 200mA 
If you have 6 motors in parallel, you need a 1.5V supply that will source 6*200mA = 1200mA or 1.2Amps

If you had 60 motors you could make 10 strings of 6 motors in series (I can draw this if you'd like, but only if you request it) So you could make 10 paralleled strings of 6 motors each. A 9V supply would work, but each string would need 200mA and you have 10 strings so you would need a 9V supply with each string drawing 200mA*10 = 2000mA or 2Amps so a 9V supply with 2 Amps should work.