Demonseed Elite, Ancient History, Jong WK, and Synner were all kind enough to post up their material for the wayward Shadows of Latin America book for all of us to finally enjoy. Be sure to buy them all dinner should you run into them, since they've put their work out there for free.

Here's the links they've provided, for ease of access:
Argentina - Peter taylor
Bolivia - Jong-Won Kim
Panama - Jong-Won Kim
Caracas - Jong-Won Kim
Aztlan - Jay Levine
SoLA Drafts - Jay Levine's, zipped files
Carib League - Jay Levine
"Other Info" - Statistics/Game Info - Jay Levine
French Guina - Mircosoft Word Format - Bobby Derie

Thanks guys. Your efforts are well appreciated.
Link to original thread in the main forums section

All of the above links and some related links from the original thread.

Shadows of Latin America (2064) (originally developed by Rob Boyle as FanPro SKU 25011):

Note that none of this material may be used for any commercial purpose without permission from the authors.
• Aztlan – written and posted by Jason Levine (Demonseed Elite)
• Caribbean League – written and posted by Jason Levine
  • Aztlan & C.L. sidebars – written and posted by Jason Levine
• French Guiana – written and posted by Robert Derie (Ancient History)
• Bolivia – written and posted by Jong-Won Kim (JongWK)
• Panama – written and posted by Jong-Won Kim
• Caracas – written and posted by Jong-Won Kim
• Argentina – written and posted by Peter Taylor (Synner)
• Uruguay – shown on Wordman's 2062 map, since annexed by Amazonia
• Peru – written by José Barbe & Hugo Medina, posted (with permission) by Jong-Won Kim
• Crime – written and posted by Jong-Won Kim
• Amazonia – written by Antonio Pucci & Peter Taylor (not released separately)
• Equador – written by Antonio Pucci (not released separately)
• Chile – written by Pavel Christiny (not released separately)
• Yucatan – written by Peter Taylor (not released separately)
• Corporate overview – by an unnamed author (not released separately)
• Tobias Grunow (~fexes) added the following via his DeviantArt page
  • SoLA Cover Design
  • Latin America 2064
  • Maps: Amazonia, Argentina, Aztlan, Bolivia, Caribbean League, Chile, Ecuador, Peru

All of the above has been formatted and compiled into a single PDF by Tobias Grunow:

• Shadows of Latin America (compiled, v1.2, highres) (direct link to a 90 MB PDF)
• Shadows of Latin America (compiled, v1.2, lowres) (direct link to a 22 MB PDF)

Other SoLA material:

• FanPro description – from The Internet Archive
  • cover – at shadowrun4.com and pl.shadowrun.wikia (artist not listed)
• Concept artwork by Kenny Barral, a now deceased Spanish-Uruguayan artist, actor, and gamer. The art was posted by JongWK in remembrance of the artist in February 2008.
  • SS1 "Customs check in Montevideo" The Salvo Palace is visible in the background
  • SS2 "Argentinean activist"
  • SS4 "Jungle run"
  • BG4 "Bomb blast during cocktail party"
  • BG7 "Chilean smuggler"
  • BG8 "Amazonian brawl" He wanted to set this one in front of a colonial church.
  • —— "Bike chase in Metropole" Check the Christ Redeemer atop the Corcovado in the background.

"Latin America 2072" (originally written for the Sixth World Almanac):

Note that none of this material may be used for any commercial purpose without permission from the authors.
• Amazonia – written and posted by Robert Derie, based in part on work by Antonio Pucci & Peter Taylor.
• Aztlan – written and posted by Robert Derie, based in part on work by Jason Levine.
• Caribbean League – written and posted by Robert Derie, based in part on work by Jason Levine.
• Peru – written and posted by Robert Derie, based in part on work by José Fernando Barbe & Hugo Medina.

Many, many, many thanks to all of you

^{Updated: 6 January 2012}

Shadows of Latin America v1.2 (highres PDF - 91.5 MB)
Shadows of Latin America v1.2-1 (lowres PDF - 22 MB)

Edit: Map of Ecuador included; Credits included.

So for the parts which have not been released - can we know why? Was the author contact info impossible to find? Did they refuse to reply (then we should try again)? Did they reply with "won't release"? If so, what was their rationale - so we can ask again with better arguments