Some Advice: Any Amateur can look at something, but only a Pro can really see what they are looking for.

Q1. Is there somewhere you can go to get help or information on how to use the program properly, or is just a matter of trial and error.

A1. Well, this BBS is one place... Try some of the links in the above phrase.

There are helpful forums within the Google Earth Community BBS.

There are also tutorials here on the BBS.

There are a number of user WEB sites.
Google Earth Blog
Ogle Earth Blog
Juicy Geography

And don't forget the "Help" pages within Google Earth itself.

Q2. I have just joined but cannot see any instructions on how to post a message.

A2. Also, look in the top right corner of a post for the word "Reply" or in a forum "Index" page for the word "Post"

Q3. I have found some place names on Google Earth that have been put in the wrong location. How can I change or notify someone to change.

A3. Make a post in this forum.