The Hornby Select Controller is a nice easy way to start out in the world of DCC, this controller has a clear 2-digit screen which allows you to see which locomotive you have selected. The Select is capable of controlling 60 Locomotives and depending on power available you can run up to 10 at once.
The Select Unit can easily control up to 40 solenoid accessories including point motors and various other items. You can also operate the first 9 locomotive functions (F0 - F8) which is plenty for starting out with DCC Sound.
For a replacement power supply you need to use the P9300 Transformer from Hornby.