Adding Clip Art
Clip art is another thing lacking in OOo. If you don't ever use clip art, you don't have to worry. But if you like to spice up your documents, you probably miss the clip art.
OxygenOffice, another free and open office suite, provides an OOo extension. This gives you a variety of clip art, from Arrows and Animals to Photos and People.
Once downloaded, you can install it as an extension: click Tools > Extension Manger. Then you can access the clip art from the OOo Gallery. There's an icon on the toolbar and a shortcut under the Tools menu.
You might also want to check Microsoft's Office Online site. You can simply browse the media, hover over the desired image and select Copy to Clipboard. Then you can paste it directly into the OOo applications.