The driver side torsion bar key area in the cross member rusted out and that side collapsed. Where can I get a replacement cross member for a 2005 AWD Astro?

Forget the online quotes, go visit the yards or call them and see if they have a second generation Astro (1995-2005) with the part you need. I frequent yards a lot, I get the best responses in person, pretty good responses on the phone, and never get a response based on some Web page input form.

If that part rusted out the rest of your van is probably ready to fall apart. Inspect it before sinking money into a rust bucket.