I was probably working in a lab at UCSF, and didn't hear about it until I watched the news on TV or listened to it on the radio.
I can't say it had much of an effect - to me at that time Elvis was ancient history, eclipsed by the Beatles and later forms of rock 'n roll. And of course disco was making a big impact in '77, and Elvis wasn't exactly a disco king, even though his size occassionally approached that of Barry White.
But, later on, about five years later, I grew to appreciate some of his early stuff, like "Jail House Rock". Good dance tunes, added variety to dance mix tapes.
I guess when I was a kid when Elvis first became popular, I couldn't for the life of me understand what women saw in him. He seemed like a conceited bore to me. But I guess he had that swagger and that shake that outraged their parents ;-). In truth he was just a country boy who had talent, was exploited, made some serious mistakes, and died a legend.