I create cool-looking skinned installers in NSIS and Inno Setup: http://graphical-installer.com/

Microsoft Visual Studio (2005 - 2022) extension for creating NSIS and Inno Setup installers with .vdproj import: http://www.visual-installer.com/

Embarcadero RAD Studio (2009, 2010, XE - XE8, 10 Seattle - 11 Alexandria) extension for creating NSIS and Inno Setup installers (C++ Builder and Delphi): http://www.rad-installer.com/

C/C++/C#/Delphi programming, NSIS/Inno Setup outsourcing: http://www.unsigned.sk/