just wondering how to get my champion add ons through steam

They should show up in your steam page for the game. You can try verifying game files. If they show up but they don't install properly try unclicking and reclicking them. Once addons like the almanac are downloaded, you can find them in the POE folder in steam. 

 

If they don't show up on steam at all, and you are a backer, go to the backer portal page to get them.

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