Hi bro,
Fan can get from Sim lin and wiring is very simple...2 wires; Positive and Negative unless you buy those come with 3 wires which the third one is use for control purpose. Regards to PS, I would advice to use separate PS as fan current is normally lower than 3W LED.
For me, I connect my 9~10Vdc PS to my 2 fans and at the same time link to the dimmer control of the Meanwell PS( to LED).
If fan PS fails, Meanwell PS switch off the output so.....LED off too to protect the LEDs overheated.