mobo and PSU will come with all the cables, CPU cooler with brackets, so you won't need any cables or brackets to buy.
many quality brands for PSU like Bequiet, Corsair, Enermax, PC P&C, Seasonic or Zalman. 500w-600w range should be enough for that spec, but if you want to add a second GFX card in future you may wish to get +700w. then you need to decide modular or non modular, guess price will determine your choice then