This aspect of interview preparation cannot be overemphasized. Do your homework. You should become familiar with the organization's products, structure, services, financial status, competitors, reputation and any recent major changes.
Many people hesitate to contact others for fear of imposing or asking for help.
The mistakes most candidates make is not preparing sufficiently for each meeting. Concisely lay out what you want to discuss. Be brief and stick to the point. Make known your career goals and objectives. Get feedback on your job-search plan, objectives and updated resume.