The authors explored the ways in which students drew on their individual theories of knowledge and knowing, or personal epistemologies, to identify and learn from multiple informational sources found on the internet. Analysis of students' think-aloud reports (during reading) and their written questions (after reading) indicated that students' personal epistemologies came into play as they were accessing, evaluating, and using diverse sources, which was reflected in their critical questioning in multiple ways. These results have implications for rethinking classroom literacy tasks in which students are asked to conduct online research to explore multiple pathways to understanding, questioning, and learning. The authors provide suggestions and instructional tools to support the development and use of students' beliefs about knowledge in complex, multisource literacy task environments.