Complex sentence: Aside from his career in music, Buffett is also a best-selling writer and is involved in two restaurant chains named after two of his best-known songs; he owns the Margaritaville Cafe restaurant chain and co-developed the Cheeseburger in Paradise restaurant chain.
Split into simpler sentences: Aside from his career in music, Buffett is also a best-selling writer and is involved in two restaurant chains named after two of his best-known songs, "Cheeseburger in Paradise" and "Margaritaville". He owns the Margaritaville Cafe restaurant chain and co-developed the Cheeseburger in Paradise restaurant chain.