[Mauzen]

If you cant script at all, dont start with such difficult things like car systems. Start with going through existing scripts, like the gamemodes downloaded with the server or simple filterscripts here in the forum, and try to understand what they are doing. Then try to modifiy them a bit, can be something total useless, just try to pawns grammar and functions. The wiki will help you, if you want to know something about a specific function: http://wiki.sa-mp.com

If you think you got the major things, and can understand (at least with the help of the wiki and some time) most scripts you look at, you can start trying to script something bigger yourself.