README: add links to cuelang.org guides

Signed-off-by: Jonathan Matthews <[email protected]>
Change-Id: I14c3a3864cb78bd53c59f3b1ecf2f9d79c22b0c4
Dispatch-Trailer: {"type":"trybot","CL":1202152,"patchset":1,"ref":"refs/changes/52/1202152/1","targetBranch":"main"}

Author: jpluscplusm

README.md

@@ -15,7 +15,8 @@ you might need to change that.
 
 ## Using
 
-TODO.
+- [Getting started using CUE in Java](https://cuelang.org/docs/tutorial/get-started-cue-java/) on cuelang.org
+- [Other Java+CUE guides](https://cuelang.org/search/?q=tag:%22java%20api%22) on cuelang.org
 
 ## Known Limitations