Modloader, Modloader MP, and most Minecraft mods are completely free. You can download most of them at the Minecraft Forum.
Modloader can be found in the modding section of the minecraft forums.
You can make it yourself. Modloader and Modloader MP will recognize the mod folder in your .minecraft folder.
no you dont
Use minecraft forge or modloader so that the mods are compatible.
You can download it possibly from minecraft forums.
Yes, Forge should be completely compatible with modloader.
It allows you to add mods that require ModLoader to your Minecraft
No. I use that mod and I don't have mod loader.
It should already be on when you install it.
no unless you have modloader
You probably didn't install Modloader correctly. Make sure you have deleted META-INF and any other corrupt mods.