Like many Pokemon fans, I made an episode guide. Mine is better though, as it comes with 20 years of hindsight and I tell you where to find the Japanese episodes as well. I think everything in each section should be self explanatory. It was all prepared in spreadsheet format, because I like it that way.

Guide to Pokemon Fansubs

Kanto and Orange Islands Watch Guide

Johto Watch Guide

Advanced Generation Watch Guide

Diamond and Pearl Watch Guide

Best Wishes Watch Guide

X and Y Watch Guide

Sun and Moon Watch Guide

Pokemon Journeys Watch Guide

Movies and Specials Watch Guide

Other Pokemon Anime Watch Guide