i am seriously disturbed and confused!!!
what are u trying to accomplish with ur gear?
anyway, for lvling, unless u can do instances every single day, dont bother with holy, u can actually heal very will with a shadow specc. anyway, start gathering spi gear, u need some int and sta, that gear is for farming/grinding, if u need to do harder quests that the spi gear cant be good enough for, get +spell dmg and +int for such ocasions, dont get rid of the healing gear u can get through quests and instances if u wanna heal, they will help when u reach 70 and wanna heal. u can get really nice +spell dmg gear through quests too, some are grp quests though, so u have to ask for help
when u reach 70, if u gonna farm with the priest, u still need spi, but try getting about lvl 67-70 items with spi as they will have good amount of spi that will help better than a lvl 58-65 items with spi.
what u need as a shadow priest is: spelldmg/shadow dmg, then int then sta then spi, spi as a shadow dmg dealer is the last u need, the most important is spell dmg, but that doesnt mean to get green items with high shadow dmg and no other stats, u need the other stats, some encounter u need about 8k-9k hp so u wont die.
as a healer u need: +healing/mana-5sec depends on which u have most, if u have enough mana/5sec go for moer +healing and vice versa, and u still need sta and int.
for prof, i recommend tailoring before anything else as it will give u best gear up tell t6, if u wan a bit more boos take enchanting, if u dont care about the extra boost get herbing to be able to gather the herbs u need for pots, and sell the extra, or get mining as it is really nice as a profitable proff, i personally have tialoring and enchanting on my priest, and mining and herbing on my alt ^^
hope that i helped.