For the purpose of clarity and consistency, the term e-learning is used throughout the paper to refer to technology-enhanced learning and information technology (IT) in teaching and learning. IT depicts computing and other IT resources. Research into e-learning has changed in focus and breadth over the last four decades as a consequence of changing technologies, and changes in educational policies and practices. Although increasing numbers of young people have access to a wide range of IT technologies during their leisure activities, little is known about this impact on their learning. Much of the research evidence, to date, of students' informal uses of IT is about the frequency of use in different educational settings and the different types of IT uses occurring among learners at school and in the home. There is little evidence of the interrelationship between them. What makes researching e-learning so difficult is the ever-changing technology itself and the increasing access to IT resources in informal settings, changing the balance between formal and informal uses of e-learning. This rebalancing not only results in a wider diversification of IT uses by learners but also a greater variability in their IT literacies and unknown variables such as the level of control of the learning activities, and contributions from third parties online. This paper reviews the wide range of technological and educational research changes that have taken place over the last 40 years, the affordances these provide, and the consequent implications for research methods and issues regarding investigating the impact of IT on formal and informal learning. Based on this analysis, strategies are proposed to help us achieve reliable research approaches and methods that take account of the eclectic nature of e-learning and the growing influence of informal learning on e-learning in education. (Contains 3 tables, 1 figure, and 2 notes.)