There are several pedigree databases for Icelandic sheepdogs. While ideally they will eventually all have the same information, each grew from a different starting point. There are differences in the dogs included, particularly as you get closer to present day. Because they utilize different platforms, there are also some differences in functionality.

ISAA Database
http://is-pedigrees.com/
more American and Canadian dogs, pedigrees, links for related dogs, reverse pedigree generator, trial pedigree, no photos

ISIC Database
http://www.islenskurhundur.com/
more European dogs, links for related dogs, pedigree generator, trial pedigrees, COI calculator, photos of many dogs

DogsGlobal
https://www.dogsglobal.com/icelandic-sheepdog/
free and paid versions, population genetics focus free version allows pedigree look up, paid adds functionality and gives mean kinship and COI in test breedings, photos of many dogs