The following are useful Links around the internet for information to help out. By no means is this list complete, but a great place to start.
Small Board Computing
RaspberryPi
BananaPi
OrangePi
Rock64
Odroid
ASUS Tinker Board
Libre Computer
Operation Systems
Armbian
Debian
openSUSE
Fedora
Ubuntu
Tools
Noobs
BerryBoot
Etcher
ApplePi-Baker
Retro Gaming
RetroPie
RetroArch
RecalBox
Lakka
Retro Units
Media Software
Other Apps for SBC
Facebook, Twitter, YouTube
RetroPie
Odroid Retro Arena
Retro-Gaming on the Tinker Board
RecalBox
Cases and More