With increasing numbers of scholarly publications, and multiplicity of publication-types and outlets, overviews of research fields have become a challenge. We bring together bibliometric methods, information retrieval, information fusion, and data visualization within a new project, INCITE - Information Fusion as an E-service in Scholarly Information Use, with the aim to develop improved methods and tools addressing emerging user-needs. In this paper we report on ongoing research within that project. (a) We elaborate on a qualitative user-study in which the emerging needs of researchers in the age of big data are explored. The study is based on interviews and dialogue with seven scholars at different academic levels. Data analysis was informed by adaptive theory, in accordance to which iterative pre-coding, provisional codes, and memo-writing were used to reach a more abstract level of analysis. A number of challenges related to the multiplicity of information sources and extent of data were identified including difficulties in keeping track of all the relevant sources; the inability to utilize extensive sets of data being taken for granted; and using data reduction strategies that at times go against the scholar’s own ideals of scholarly rigor. In analysing these difficulties, we have identified potential solutions that could facilitate the process of forming overviews of different research areas. (b) An example of such a solution is presented, which is builds on the Dempster-Shafer Theory and is designed to allow for interactive individual ranking of information sources in the process of a coordinated search across different information sources.