@Kase I think he wants s0biet.
For vehicle mods I would recommend SAMI (San Andreas Mod Installer)
For sound mods, well really most people pack this themselves, you can normally just throw them in the designated location of you SA folder and replace the files, normally sounds mods come with a readme to help you out.
Texture mods, well depends on the textures, most particle mods come with the instructions and pre-packed so you can just replace the files in the designated folder, but if it's like a single texture, ex: radar overlay, sniper scope, etc. Then you may want to use IMGtool.exe, can be found
here.
Most mods normally come with instructions, because they're mostly unique to different sections of the games. (Models, sounds, textures, buildings, HUD, Radar, blah blah.)
Another great useful source for instructions would be...
http://www.gtagaming.com/forums/showthread.php?t=68413