Blogs (and other information sources) are recommended to a user based history of user's online activities. The system: (1) processes the user's web history, (2) identifies blog posts (and web pages) that link to pages read by the user, (3) generates multiple relevance scores for each identified post/page, and (4) produces multiple rankings of the corresponding source blogs (and web sites) by aggregating individual relevance scores (or combinations of relevance scores), according to users' preferences. The system allows the discovery of information sources that are likely to be interesting to the user and allows sources lost in the “long tail” to be seamlessly discovered.