As stated in my other utility threads, this is awork in progress. PM me if you know of another or a better program than one I have listed here.
Thanks to : MrDeathLlama
Valve Hammer Editor 3.4
Hammer is the best editor for any Half Life mod.
Valve Hammer Editor 3.5 Beta
Update for 3.4. Includes model rendering support. Includes updated HL FGD
Compilers and Compiler Tools
Supiior compilers than the default Hammer qtools. Used by many. Can be used with Batch Compiler for a very easy compile.
Batch Compiler is a Front End program designed to compile all your maps in the simplest and fastest way possible, batch files. The program works on Batch Compiler Specification (BCS) files which are dynamic configuration files capable of specifying almost everything in Batch Compiler, from the switches, to the way the batch file is written and what is written where. Batch Compiler comes with specification files for the current Source Tools, Zoners Tools, the old Quake Tools, HLFix, RESGen, Map Backup and many other programs. Each switch contains a brief description on what it does to help make everything easy and centralized.
Game Data Files (.FGD)
Required to make Half life maps. Included with newest version of Hammer Editor.
Required to make Zombie Panic maps. Included with current version of Zombie Panic!
MAP viewer is a utility designed for fast accurate 3D previews of .MAP files.
BSP viewer is a utility designed for mappers for previewing Half-Life BSP files and technical information about how they are being rendered. This is meant to help mappers find problem areas in their BSP files that need to be optimized
GCFScape is an explorer like utility designed to allow users to browse Half-Life packages and extract their contents. GCFScape supports .gcf, .pak, .wad and .bsp packages and runs independently of Steam.
RESGen is absolutely necessary for getting your map up on a server if you want it to download fast if it has custom content. Speeds can sometimes reach as fast as the server and client can take. (assuming there is a fast download server set up)