Josefjakobs.info – A lifelong project into researching the life of Josef Jakobs by his Granddaughter. This blog has numerous posts concerning Bella in the Wych Elm and has some absolute gems of information and a ton of fascinating resources. She also straightens out many misconceptions and repeated falsehoods, often through discoveries unearthed by her own research.
Wikipedia – Always a good starting point to nail down many facts of the case.
Amazon – Murder by Witchcraft – Not a great book all told but it’s one of the few. The writer addresses both Bella in the Wych Elm and Charles Walton, but unfortunately, is not known for his historical accuracy. Even I know that many of his ‘facts’ concerning Charles Walton are pure bullshit. However, it’s one of the few books on the case if you like to have books.