It's not been released yet but it was reported that the pricing would be competitive, compared with what you normally pay for high speed internet in North America. Starlink may have different price strategies in different areas but it's just my speculation.
Not really. For the foreseeable future, you will need a satellite receiver from Starlink to convert the signal to wifi, which will enable you to connect your phone/PCs.
Well, looks like they are starting private beta, then public beta with high latitude areas, then moving toward equator. North America is expected to be covered by 2020, and worldwide coverage starts in 2021. Exact availability, you will have to check starlink.com for details. We suggest you sign up on their homepage for updates. They just need your email and zipcode.