Today the NLRB released a mobile phone app for both iPhone and Android users. [Press release] I now have it on my iPhone. And it works pretty well.
There are separate sections for employees, employers, and unions. Some portions are quite general, and others are relatively sophisticated. Certainly no substitute for good legal advice.
There's a button for displaying the NLRB regional office nearest you. When I tried it, I got New York, Buffalo, and New Orleans. And I live in Portland, Oregon. Oh, well, it's a free app.