Games for Windows LIVE Disabler -> disables GfWL and moves your DLCs into your game folder.ArchiveInvalidation Invalidated -> does the whole 'ArchiveInvalidation'.Fallout Mod Sorter (FOMS) -> another load order helper.Better Oblivion Sorting Software for Fallout3 (BOSS for FO3) -> sorts your load order automatically.FO3Edit -> detects Conflicts between Mods, a powerful tool for Mod editing.

If you moved your DLCs from the Live location into your Data folder or if you use FOSE, read the 'Point VII) Where Have All the Savegames Gone '.

Fallout Script Extender (FOSE) -> many Mods require its additional scripting commands to work.

Fallout Mod Manager (FOMM) -> optional Fallout Launcher providing very useful Modding-Tool, like BSA browser, BSA creator and TESsnip.

Currently in beta stage and regarding tools not as powerful as FOMM, but more features will follow

Nexus Mod Manager (NMM) -> The official Mod Manager.

a 'Data Compression Utility' like 7zip, WinRAR, IZArc or TUGZip -> to extract file archives.

I ) Mods Prerequisites - Tools that make life easier Must Haves

Nexus mods d3d9.dll fallout 3