This may be the best place to start, if you're not already aware of a case or statute that triggers a legal issue you want to write about. Browsing papers, magazines, journals and blogs will give you a sense of the most current issues in bioethics, and may spark an interest in researching further.
Below is a non-exhaustive list of Bio Sciences and Bioethics journals
The Hastings Center Report - by the Hastings Center
IRB: Ethics & Human Research - also published by the Hastings Center, this publication explores issues in research with
List of Bioethics Journals - by the Bioethics Research Library at Georgetown