I suggest starting with some of the few classical resources that exist about Hestia — the Homeric and Orphic Hymns honoring her. Then, I also suggest researching her Roman counterpart Vesta and how she was paid cultus in both the Roman Republic and later the Roman Empire in pre-Christian times.
It is only after that that I would suggest looking on the internet for websites and blogs (such as mine) where Hestia is often mentioned. This would help you gain more information about this Goddess in the modern era.
However, I would advise avoiding the trap that many people fall into in thinking that Hestia is ONLY a hearth-goddess or ONLY a fire-goddess. I would advise remembering that she was not only in charge of the hearth within the home, but the civic hearth whose fires were never allowed to go out because it was literally seen as the heart of the city-state. This would extend to her having influence in civic life as well as in the home. In the modern day, I would say this COULD also involve social justice and protecting the state from unfit leadership.
Hestia – because she is less well-known than others of he Hellenic pantheon – is a goddess that seems to invite a closer look in order for her to reveal more of her nature.