[Weirdosport]

1. In game type /save, then exit and look in your GTA directory for "savedpositions.txt". You don't have to install a script for this to work.
2. They're all fairly good, just use the search button, looks at the command lists and read the replies.
3. This and the wiki are the best places to go.

The 3 most important wiki pages IMO for a beginner:

Main Page
Functions List
Tutorials