Van Halen was born in the Netherlands, but his family moved to Pasadena when he was just seven years old.
Norman Harris of Norm's Rare Guitars in Tarzana recalled selling Van Halen two guitars back in 1977.
He had a remarkable influence on future generations of musicians, he said.
"He showed people what a guitar could do, that most people weren't doing," Harris said. "There were so many young people who started playing once they heard Van Halen and were really inspired to go on to great things."
"Pasadena" was trending on Twitter as older residents of the San Gabriel Valley reminisced about seeing Eddie and his brother Alex, as well as bandmates Michael Anthony and David Lee Roth, around town before they hit it big.
Some pointed out the words "Van Halen" were written in a concrete sidewalk near the Pasadena neighborhood where the Van Halens lived.
Photos on social media showed some fans had created an impromptu shrine with flowers and candles at the sidewalk
The city of Pasadena sent out a tweet expressing condolences:
"We are saddened by the news of Eddie Van Halen's passing. Pasadena was home to Eddie and his family for many years. Our condolences go out to the entire Van Halen family."