Structural data on protein-DNA and protein-RNA interactions are indispensable in molecular biology research. In this article, we review available databases and other web-based resources devoted to 3D structures of protein-nucleic acid complexes. First, we describe the core databases that collect and disseminate experimental data. We then review derivative databases focused specifically on structural data on protein-nucleic acid interactions. Finally, we provide an overview of several useful web servers for structure prediction, analysis and comparison. Tools for investigating protein-nucleic acid complexes are relatively scarce. This is primarily because the methods that integrate structural information from both proteins and nucleic acids are in short supply. However, the emerging AI-driven techniques for structure prediction are expected to boost the development of such methods.