Seeking Assistance for Sourcing Candidates for Interviews

I’m looking for guidance on how to effectively source mid-level candidates (3+ years of experience) for Sales and Business Development positions in the Telecom sector in Germany. My experience with sourcing candidates for commercial roles is limited, and I currently don’t have access to LinkedIn Recruiter or paid job platforms. What strategies should I consider? Are there specific tools or websites that could aid in my search? Any advice would be greatly appreciated!