The Centers for Disease Control and Prevention (CDC) has great information on the Covid-19 vaccines, including a FAQ page. Another CDC resource will direct you to state Department of Health websites. Those sites will help you determine when you can get the vaccine in your area.
This website (covidvaccinefacts.org) will also be continually updated to provide trusted information on all Covid-19-related matters, including vaccines. You can find an interactive state map with links to state-specific guidance on vaccine availability and distribution here.