Every guest posters, sponsors are welcome.
If you want to publish your guest post, sponsorship and backlinks in my site then you can contact through mail (email@example.com).
Also, everything what you want to publish must follow google adsense communuty guidelines.
Link 1:- AdSense Program policies – Google AdSense Help
Link 2:- Eligibility requirements for AdSense – Google AdSense Help
Link 3:- AdSense policies: a beginner’s guide – Google AdSense Help