Hi and welcome to the community!!
I can try and help you but you did't give that much info, it usually helps to provide at least screen shots:
1) Guides - There is a fair bit of information available. I have summarized a few of them here.
Wiki
http://www.esenthel.com/wiki/index.php?title=Main_Page
Since a lot of your questions are on the world editor, here is the link to the world editor section specifically. It is for 1.0 so it looks a little different, but same basic idea.
http://www.esenthel.com/wiki/index.php?t...rld_Editor
A few video tutorials:
http://www.esenthel.com/community/forumd...hp?fid=104
User Gwald put together a nice little summary
http://www.esenthel.com/community/showth...ight=gwald
2) For your question about the character, I am assuming you are saying you have a character you exported from 3DS or Blender or something and you are missing the material and maps for the character. If that is the question, then what you need to do is double click on the object to enter the Object Editor. Also, in the same file tree as the object, there should be a child of the object that is the material. If not, create a new material. Double click on that material and you should see the material editor on the right. Open the folder that has the Materials for the model and drag and drop the Diffuse, Normal, Bump, Spec, etc.. maps to the appropriate box. That should do it.
3)To extend your world, there are a few things here. In the World editor, the first thing you do is select Terrain. Next, what I like to do is change the Visible Radius a little higher. Then click the Del /Add button. Now drag and drop the materiel you want to extend the world with in the Material box next to Del / Add. Then use the LEFT mouse button to add the land. To move around, you hold down the space bar.
Hope this helps.