symphonicpoet
Moderator
Since this came up in another thread I thought I'd start a thread dedicated to listing suppliers of civilians and fauna for your sci-fi adventure gaming needs. As folks add new finds to the thread I will gladly add them in to the top post. 
Civlians
Blind Beggar: Outlands, Amphibious Aliens, Dune Tribe, many humans and aliens of many sorts in several ranges.
CP Models: Human and alien civilans in the 28mm Sci-Fi range. Also Scum and Smugglers to inhabit every wretched starport hive.
Crooked Dice: Colony 87 civilians. Enough said.
Forlonrhope (ne Moonraker): Some civilians in Future Warriors range. Formerly also Space Lords civilians. (Hoping these come back.)
Lead Adventure: Astropolis in particular
Ramshackle: Suitable civilians come and go spread through several ranges. Some great civilian vehicles.
Rogue Stars: A few adventurers that might serve as boss grade civilians.
Fauna
Knightmare Miniatures: Modern takes on classic space monsters. (Also some very nice mercenary and armed adventurer types.)
Krakon Games: Enormous selection of alien fauna in the Stargrind range, including RT inspired "Grok." (Also some very nice adventurers.)
Ramshackle: Dungers. Lots of dungers! (And steampunk mercenaries and adventurers.)
Wargames Foundry: Some of the fantasy creatures make suitable alien fauna. (Most notably the terror birds.) Further, if there are humans you can also expect human livestock, so why not pigs in space?

Civlians
Blind Beggar: Outlands, Amphibious Aliens, Dune Tribe, many humans and aliens of many sorts in several ranges.
CP Models: Human and alien civilans in the 28mm Sci-Fi range. Also Scum and Smugglers to inhabit every wretched starport hive.
Crooked Dice: Colony 87 civilians. Enough said.
Forlonrhope (ne Moonraker): Some civilians in Future Warriors range. Formerly also Space Lords civilians. (Hoping these come back.)
Lead Adventure: Astropolis in particular
Ramshackle: Suitable civilians come and go spread through several ranges. Some great civilian vehicles.
Rogue Stars: A few adventurers that might serve as boss grade civilians.
Fauna
Knightmare Miniatures: Modern takes on classic space monsters. (Also some very nice mercenary and armed adventurer types.)
Krakon Games: Enormous selection of alien fauna in the Stargrind range, including RT inspired "Grok." (Also some very nice adventurers.)
Ramshackle: Dungers. Lots of dungers! (And steampunk mercenaries and adventurers.)
Wargames Foundry: Some of the fantasy creatures make suitable alien fauna. (Most notably the terror birds.) Further, if there are humans you can also expect human livestock, so why not pigs in space?