Analog to Digital questions

Hi folks,

Would love some help here as I think about recording vinyl to computer.  A few questions:

  1. My phono stage is built-in to my pre-amp (Classe CP-35).  The pre-amp has RCA and XLR outputs for connection to an amp, as well as a "tape out" connection.  Can I use one of those to connect to an Analog-to-Digital converter (ADC)?  Or is the pre-amp output too "loud" for the ADC?
  2. Is it important to have an input gain control on the ADC?
  3. Is there such a thing as a device that does both A->D AND D->A?  In the long run, I'd like to use the computer to play music as well as record it.  Or does everyone buy two devices?

Thank you!