Well I just played about an hour and a half more. I've just found Christine and brought her back to the "fountain", spoken w. Elijah and gotten directions for the Gala. Am I at least half way through??? Prolly not.
I'll break it down into dummy terms. (Dummy as in the very very basics of the story, not insulting you.)
1. Radio in the Abandoned Bunker
2. Awaken at the Sierra Madre
3. Find Christine, Dog, and Dean Domino
4. Take each of them to their positions required and fire off the Gala
5. Enter the Casino
6. Kill or Help your partners to recalibrate their collars
7. Get to the Madre vault.
Also, as a positive, once you fire off the Gala and get into the Casino, the difficulty of Dead Money takes a drastic nose dive into easy town.