I would advise staying away from celebrity sheiks, those with deviant ideologies and those with weak knowledge.
In short, I would stay away from
following speakers:
Hamza Yusuf (sufi deviant) and his institute
Zaid Shakir (sufi deviant) and his institute
Yusuf Estes (weak knowledge)
Zakir Naik (weak knowledge)
nouman ali khan (liar, deviant) and his institute
yasir qadhi (liar, deviant) and his institute
suhaib webb(liar, deviant)
Others here will disagree but those who do lack the knowledge to differentiate between lies and real knowledge because only knowledge they have is from these.