The present study investigated how 6 Korean ESL graduate students in Canada used a suite of freely available reference resources, consisting of Web-based corpus tools, Google search engines, and dictionaries, for solving linguistic problems while completing an authentic academic writing assignment in English. Using a mixed methods design, the study examined the processes and outcomes of combined use of concordancers and other reference resources by the participants and their perceptions of the reference suite as a means of writing assistance. Results showed that while the reference suite served as an effective cognitive tool extending the cognitive powers of the participants in solving lexical and grammatical problems, the individual resources in the suite were each shown to have unique functions for which they were best suited, suggesting that concordancing may optimally be consulted in combination with other resources. However, some participants also experienced difficulties in using the tool stemming largely from the nature of their writing tasks and writing stages, and different goals and needs arising from them. This paper concludes by discussing theoretical and pedagogical implications of the findings.