Who was the Companion whose mother gave birth to him while she was circumambulating the Kaaba, and is there a website that provides information about the Companions?

Hakim ibn Hizam, may Allah be pleased with him, was born inside the Kaaba and lived for 120 years, as stated by Muslim in his Sahih. Al-Hakim also mentioned in his Mustadrak that Ali ibn Abi Talib, may Allah be pleased with him, was born by his mother, Fatimah bint Asad, inside the Kaaba.

To learn more about the lives of the Companions, one can benefit from books available on Islamic websites. Among the useful books are "Siyar A'lam al-Nubala'" by Al-Dhahabi and "Al-Isabah fi Tamyiz al-Sahabah" by Ibn Hajar.