Virtual worlds, which allow users to create and interact with content in a 3D, multi-user environment, growing and becoming more integrated with the traditional flat web. However, little is empirically known about the content users create in virtual world and how it can be indexed and searched effectively. In order to gain a better understanding of what users are creating, how they interact with it, and how frequently it changes, this research presents a virtual world crawler. Much like flat web crawlers, the crawler in the virtual world explores the content space, gathers information, and stores both content and metadata for use in research or a cross-world search engine. Over the course of four large-scale surveys spanning 15 months and 2 worlds, the crawling system gathered information from tens of thousands of regions about hundreds of millions of user-created objects. Analyzing this data has led to insights into how users are utilizing virtual world platforms, how frequently they change, and how they can be efficiently explored. This is the first publication of a large-scale virtual world content crawler, and lays the foundation for future work in the area of virtual world research. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]