The following links are provided to help you understand ElasticSearch, Logstash and Kibana better. These are not maintained by the SP-Solutions team but by their respective owners. The SP-Solutions team can help answer questions (via issues) about certain aspects, but it is recommended to participate the in the forums for the respective sites to ask experts in each functional area.
If any of the below are not suited to your learning style or do not answer the question(s) that you have, Google is your friend.

The below should make you highly dangerous: