When I do a search for
installer
at Softpedia.com I come up with a bunch of them. I don't know which would be most appropriate for your game.
I think all the installer needs to do for your game is...
- unzip the file and prompt the user where to install it. You could offer a default location of C:\SlipSpace or a SlipSpace folder inside the My Documents folder. I'd avoid installing to C:\Program Files.
- make a desktop icon and an icon in the Start menu.
- avoid triggering an antivirus.
You might also ask other developers what programs they use as installers for their games.