The Go Programming Language (https://gopl.io) is what I've had at my desk the past few weeks while learning. Also whenever I get stuck I search Github code for a term like "json.Unmarshal" to find how others have done something. And otherwise just duckduckgo'ing "golang <search term>". Also you'll hear a million times to check out Effective Go and The Go Tour (on the official Golang site). Those are good but I appreciate them more now that I've got a good foundation