Well, Most folks *guessing* probably use corel draw or adobe to do thier graphics editing. Both i believe allow you to save or convert file in TGA ext. I myself use adobe to edit graphics. I allo
ws for alot of effects and variable graphics options while maintaining a fixed size and resolution. alternately there are conversion programs thatwill allow you to convert files from say jpeg to .tga. I use one of those as well at times . . .
Adobe Photoshop 5.5+ is great, as is Corel Draw. Also the conversion tool, called Easy Graphics Conveter is a good tool for converting existing graphics files to .tga formats.
Adobe and Corel both are expensive programs, though they are well worth the price. Believe you can download trial versions for each of those from thier web sites.
Graphics Coverter Adobe Photoshop