=Sarc=

GR.net Modding Articles - A great list of various tutorials
Piggyson no longer hosts a GR modding website.

Notable tutorials:

Mapping
Trees Part 1: Canopy Trees
Trees Part 2: Fir Trees
Trees Part 3: Palm Trees
Papa6's Beginner Map Making
Javaman's Smart Tools 2.0 - Compilation of 3DSM scripts to aid with modelling and tagging
Creating Landscapes with Heightmaps

Characters
Exporting a character to GR
Skinning

Igor
Igor for Dummies
Scripting Technique - Using Groups
Mission Conception by H-Hour

Vehicles
Vehicle tagging

Weapons
Pain's Tutorials - Click on the drop-down list on the left for modding videos

These are some of the tutorials I've used while modding GR. Please post other tutorials that have been helpful to you.

H-Hour

I spent a lot of time with that technique of creating landscapes with heightmaps. Very cool. One problem I could not rectify, though, is that it places all the verteces off grid and I was having the most difficult time getting them back on grid in areas where I wanted to interject something specific like a cliff face. Still, a very nice method if you're not retarded with snaps like I am. You can get very complicated with your heightmap and get very specific results (I had the basic ground for a whole map done in three days).

I would also recommend spending a lot of time with the LevelBuilder.pdf included on the DS cd. It's a great reference for when you go to create outside of a tutorial. Helped me work out the details for exportfirst models and scattering with trees.

Cool links Sarc. Oh, and Javaman's Smart Tools: AWESOME! This map I was working on somehow got it's sherman level deleted and it was just a few clicks till his smart tools had a new one set up and working for me.

H-Hour

Mike Schell's Intro to Map Making Tutorial

Also, I think this is the link you want for the Mission Conception Guide

H-Hour

When GR.Net went down I was reminded of SanSite. Backups of lots of tutorials and other helpful files for modding:

SanSite