You get a secretary right when you start, whether you're just a summer associate or just a first year attorney or whatever. The work you give them will be pretty minimal, since you're at the bottom of the food chain. They're basically there to answer your calls and maybe type something up if you're in a jam.
Be very nice to your secretaries. I worked in a firm, and saw attorneys mistreat these people, and not realize they were shooting them in the foot. First, when you're a summer associate, they absolutely ask your secretary how you are, what kind of person you are, how you treated him/her, ect. Being an ass to a secretary can screw you out of a job offer. This also applies for when you interview. The secretary that offers you a seat and any thing to drink is making opinions of you, and you can be almost sure that those opinions will be voiced if they're bad.
As an attorney, it's just common sense that if you treat your secretary well, she'll be more likely to go above and beyond the call of duty for you. If you're a total d*ck, then they're clocking out at 5 pm as often as possible.