The CT Humanities Council is a wealth of info for cultural non-profits- arts & heritage alike. Check out their resource page to start with.
Tech Soup:This is a full-service site with low-cost or free technology for your non-profit, as well as articles & research blogs to help you in making technology decisions. We use it! It could help your organization too!
Pro-Bono Partnership- Need Legal guidance for your non-profit, or actual legal action? They offer great workshops for a variety of non-profis too!