lockpicking

[slice3]

even it's not a discussion about interface or add-ons, i want to ask this question for the reason : i'm not participating on many forums and i hate to have registered everywhere.
So, here is my question.

i'm an ally rogue but i don't know how to lockpicking.
What i need and from where to be able to use this talent.
i found few lock boxes, but i don't knwo how to open it.
please someone wrote a quick how-to fer this.

thank you