I'm just getting started and found these charts that seem helpful if you can't find the correct Citadel colors: (used in Sorastro's tutorials)
http://www.tinyworlds.co.uk/blog/paint-comparison-chart-citadel-vallejo-game-colour/
http://www.dakkadakka.com/wiki/en/Paint_Range_Compatibility_Chart
http://cdn.acrylicosvallejo.com/da452dd99dbe2199bcad5462114f55bf/cartacolor_ModelWash.pdf
--------------------------------------------------------------
List of all paints used in the Sorastro videos:
https://www.youtube.com/user/Sorastro/videos
--------------------------------------------------------------