Can you post a kind of tutorial like the one MIC posted for the Dev tool install and config (YAGARTO, TURTOISE, ECLIPSE, etc...)?
please. 
I know it takes time but it may help lot of people like me.
thank for your precious time.
Not until next week because I have no Eclipse at home right now

But if you right click on your ypod project (or any file(s)) you will get a menu and there you should have "Team"->"Update". That will update your current selection in Eclipse. Like Jesper wrote, this will not overwrite your changes. If there are no conflicts you will get your code and svn merged automatically. Otherwise it will tell you that there are conflicts that you need to solve manually.
You should also find "Compare" so you can compare your file against svn, "Replace" so you can overwrite your file with a svn version etc.