You should learn scripting from the beginning. I suggest you go for the easy scripts to begin. Like the beggining. Then you can move slowly up levels. I really do not support using others GameModes(though, people made successful servers by using a gamemode downloaded from SAMP forums), so I suggest you go on ******* and SA:MP Wiki
[ame]http://www.youtube.com/watch?v=eMXxdUaTcNU[/ame]
Quite Old Tutorial, back in 3 years. If it works for you. Then try it
... and This is a brand new Tutorial of scripting from 2011
[ame]http://www.youtube.com/watch?v=CRrF5O6NfEs&feature=related[/ame]
Thus, if you want to add new maps into your game, you can download MTA at
THIS PAGE.
Then go to map editor and start mapping(NOTE: I will not submit a tutorial, because MTA:SA offers a tutorial in game).
Then you can add them into your PAWN script by doing exact the same as in this video.
[ame]http://www.youtube.com/watch?v=MOo9G0ynLkc[/ame]
If you get the scripts and how to do it, you can find more scripts at
SA:MP Wikia Scripts CLICK
Please notify that it takes patience, efforts and even a piece of yourself to create a well developed SA:MP server.
Hope I helped you
Good luck creating your SA:MP server