Just my 2 cents
If you have changed the ALT on the car, did you charge the battery before you started the car? Are you sure it is an ALT issue and not another battery or starting issue?
What does the car do when you try and crank it over?
1. Nothing
2. Click
3. Struggle to turn over
4. Grinding or whining sound.
You also said no voltage is going to ALT, check all the battery post connections.
Let me know so I can identify if it is definately the ALT.
**Working PART-TIME for Carjunky for a while, Please bare with me =)**