This website contains all the extant Icelandic family sagas using modernized Icelandic spelling, with the Old Norse versions and translations into English and other languages made available where these exist in the public domain.
An online academic database used by universities worldwide that is a superb resource for History students. To view full articles, you will require membership.
This searches internet sites for academic articles and books. It often only provides one or two pages, but it is often enough to find quotes and bibliographical details.