I'm currently leveling a Prot. PvP/PvE Paladin (Blood Elf)
I was wondering what professions I should take up, since I both PvP and PvE.
I was thinking Mining/Engineering?
Although I already have mining on my Warrior, I don't see the need to take it up on my Pally.
I heard Engeneering was hard to lvl, but It seems pretty useful.
Any ideas on what I should do?

Thanks

Mine has always been Eng/JC, but if you want stats at 85, nothing will beat JC/BS.
Eng/BS also works, as Eng is always fun.

I would say enchanting and blacksmith. They go together the best and belfs get a nice bonus to enchant.

enchanting and jewelcrafting will give you nice combo and only crafts for rings+earring buffs that will be very helpful plus you get a racial bonus on enchanting

Well if you want to make lot's of money I recommend Skinning/herb collecting. If you want to do something more practical go for blacksmithing/enchanting or engineering/blacksmithing.