are there prebuilt 3d objects?

im a newb.

is there a place to get free prebuilt blender objects? Like trees, houses, roads, etc? so i dont have to reinvent the wheels?

http://e2-productions.com/repository/index.php

how do i use these ojbects in my current project?

First open the file with the object already in it (The on you want to bring to your project).

Then select the item you want in your project (Right click it). In the editing window, look for the object name, like this Ob: namehere (You may wish to rename it if it is something like ‘Cube’)

Remember that name. Now go to your project, and go to file>append or link.

At the bottom of the window, make sure ‘append’ is selected, then navigate to the .blend file containing the object. It will open like a folder. Select ‘objects’ then find the name of the object you want in your project, and select it, then hit the ‘Open’ button.

Thats all there is to it!