So my maxima, ever since I bought it, has had a ton of play in the steering. I can easily wobble the steering wheel between 2 or 3 inches without really affecting the direction of the car.

Where do I start?

Sway bar end links, control arm bushings and ball joints

It's most likely the tie rod ends. That's where I would start.

All of the above.

my steering wheel is really loose...i ask a mechanic but he was unsure...

then you should have went to another mechanic since this one doesnt know basics...

i would start with the easiest / cheapest fix first.
start with the endlinks parts are cheap and relatively easy to do.

my steering was worse than my dad's olds 98 (very vague, too light)

i did the endlinks and sway bar bushings and it feels MUCH better.

'99 steering rack.

I had a ton of slop and it turned out to be the steering rack bushings allowing the rack to move. They were ruined from a fluid leak.

tierod end and ball joints,also check the rack