The World Wide Web offers a lot of information that has been provided by laypersons instead of experts or professional journalists. This raises the question how Internet users perceive credibility of online authors and which information on the source influences the users' selection and processing of texts. Our study investigated the effect of self-reported expertise, community rating, and age of weblog authors. In an online laboratory experiment, information seeking behavior of 60 participants on a science weblog was analyzed. As exemplary scenario, the discussion on the effects of violent media contents on children was chosen. Results showed that authors with a high level of expertise (operationalized by the author's self-reported profession) were rated as more credible and their texts were selected for further reading more frequently. This suggests that self-reported expertise emerges as a strong cue for information selection, whereas there was only partial evidence for the importance of community ratings.