This is really helpful to diversify the current oss tools.

Does anyone know good sources for creating a SBOM?

Depends exactly what you're trying to create it for. I advocate for doing it during the build process rather than as a step after.

We open sourced a few tools that do it automatically for containers:

https://github.com/chainguard-dev/apko

https://github.com/chainguard-dev/melange