SEP entry on free will
IEP entry on free will
SEP entry on moral responsibility
There are a number of great Philosophy Bites episodes worth listening to, including those with Dan Dennett, Paul Russell, Thomas Pink, and Adina Roskies. (If you're not familiar with Dr. Roskies, you should check out her website. In addition to some fascinating publications, two Ph.D.s (one in cog sci and one in philosophy), she appears to be quite the badass philosopher. There are pics of her climbing up an icy cliff and preparing to fly a plane.)
If you know of other online resources that might be helpful, please let me know.