Linear vs Switching Regulator for Computer (22VDC to 12VDC @ 1A)
Integrated DC-DC buck regulators for 12 Volts 1 Ampere do exist, from manufacturers like Recom, R-78C12-10. These are drop in replacements for the popular 7812 type linear regulators - thus, totally integrated packages, as desired.
Yes: If your load is pulling 1 Ampere at 12 Volts with 22 Volt source, the regulator is dissipating (22 - 12) * 1 = 10 Watts as heat.
If desired power quality is not met by the switching regulator chosen, a hybrid approach, such as using an adjustable integrated switching regulator set to 14 Volts or so, followed by a low drop-out linear regulator, would give the best of both worlds - low heat, yet low ripple.