Alright then, well, first off, let me warn you:
Modding is not for noobs

It is serious stuff that you need to put your time into.
Don't expect to be able to make a great mod in less than a week.

Alrighty, now that's out of our way.......
Modtools download: http://starwarsbattlefront.filefront.co ... s_PC;57352
Install those, the default directory is C:/BF2_Modtools. If you want to install them elsewhere, make sure the directory has no spaces in the folder name.
I.e. BF2_Mod Stuff won't work, but BF2_Mod_Stuff will
READ THE DOCUMENTATION (found in C:/BF2_Modtools/documentation) THOROUGHLY, starting with the Getting Started doc.

Some other programs you may find useful:
GIMP: Image editing program. Used by modders for skinning units.
PSPad: Text editor (like wordpad, but a lot better), and hex editor

After you've followed that, explore the assets.
Most of the files in the assets (except for a few) can be opened with either wordpad or Photoshop/GIMP.
Some different kinds of folders you may encounter in exploring the assets and what are in them:

odf - Contains the .odf (Object Definition File) files.
These essentially define the objects, what they are (prop, vehicle, infantry, cp, destructable building, etc), what they do, and what model/geometry they use.
Opens with wordpad.

msh - Contains the .msh (mesh, or model) and .tga (textures for the models) files.
Basically, the odf calls for a mesh in this folder, and the .msh file calls for a .tga texture to use on the model.
.msh kinda opens with Wordpad, fully with hex editor. TGA's open with Photoshop or GIMP.

req - These contain the .req (required) files.
Every unit, vehicle, and turret needs one of these. The whole side also needs one.
Read the Jedi Creation Doc for more information.
Opens with wordpad.

effects - Contains the .fx files and some textures.
.fx files are basically effects, such as explosions, fire, or rocket trail effects.
Opens with wordpad.

munged - The zaafbin, zaabin, and anims files.
These are extremely confusing. I wouldn't recommend editing these at this point.


After you've got the basics down (adding objects, messing around with terrain, etc.), you may run into some more specific problems.


What to do when a problem isn't covered by the docs:

1) Use the search function. Yes, the search is wacked up right now, but when it clears up you'll see how useful it is.
2) Check the Modding FAQ, found here: http://www.gametoast.com/forums/viewtop ... =27&t=3497
3) Post a topic in the modding forum
Now, before posting a topic on GT, look around, learn to ropes of the community there.
When posting, don't talk remotely like a noob (no "u" instead of "you", or any other IM abbreviations).
Say what you want to say with proper spelling, grammer, and all that.
If you use some higher vocabulary, people will respect you more.
Make sure you post in the right forum, too!
-Briefly describe your problem, what you did, what happens (specifically, not just "it crashes"), and post your error log.
-People will often ask for an "error log". This is a log of errors (duh) that a program called BF2_Modtools.exe produces.
Go to your C:/BF2_Modtools directory, and copy the BF2_Modtools.exe
Place it in your Program Files/StarWarsBattlefrontII/Gamedata folder.
Run it. A windowed version of SWBF2 should pop up. Play your map, then close out of the program.
Go to Program Files/StarWarsBattlefrontII/Gamedata
Open up Bfront.txt, and post the log in your topic.
-If, after munging, a log pops up with ERROR messages, then post those too. However, WARNING messages can most often be ignored.



Misc. Notes:
-The best place to look for help on side editing would be the Jedi Creation Doc. Read this first before doing any side editing.