Well said, Tris. Hopefully, you’re beginning poetry writing class will help you sort out some of your problems. I would be very wary of free-verse poetry at this point.
Let me start with technical considerations, since those are easier to explain,.
For me, meter is one of the most important technical considerations of poetry, whether free or formal verse. Having a good ear for meter not only helps you in poetry, but it immensely helps you in prose writing as well. Nabakov also stands out for me as a prose writer with an incredibly well-tuned poetic ear. First, learn to understand meter. (You will no doubt learn this in class.) Learn what an iamb, trochee, dactyl, anapest, spondee, etc. are. Listern to how they sound and what kind of “backbeat” they form in your poetry. Read Robert Frost’s “Stopping by Woods on a Snowy Evening” and you will hear what an iambic meter sounds like. This poem is particularly strict in its meter, perfect to form the quiet, lulling “backbeat” for the words.
Second, the sounds of the words themselves are important, of course. Not just rhyme, but consonance, assonance and alliteration. Read, read, and read more poetry and pay attention to how authors apply these effects. Listen to the broad, open “ohs” in the start of the aforementioned Frost poem. But be careful not to overuse it as well.
Writing poetry is partly being a musical conductor. Besides image and content, you have to establish mood and feeling through rhythm and sound. Good free-verse poets do this as well.
On to the creative side. That’s a bit harder to explain. In poetry I look for several things. One is creative, lasting imagery. It needn’t be flowery. In fact, it’s the simple, unexpected images that cling to my memory the most. Tris’s Pound example is excellent. “In a Station of the Metro/The apparation of these faces in a crowd/Petals on a wet, black bough.” Wow. Beautiful. And listen to the sounds and rhythm here. Notice how the last line has such a nice finality. The monosyllables of “wet, black bough” slow the poem down to a halt. The near-rhyme of “bough/crowd”, the “petals/wet” sounds. Just gorgeous. And, no, I don’t think any of these are coincidences. They’re fully intended to be there.
Direct, unexpected, simple imagery is powerful. Avoid trite sentimentalizaiton. This is the most difficult thing for me, in my poetry - where does one cross the line from sentiment to sentimentality? When is one trying to make a real societal critique and when is one sounding like an angst-ridden teenager? It is difficult.
I find the first rule of writing applies even more to poetry. Write and rewrite, rewrite, rewrite… Work out that first impulse. Get some basic ideas down for imagery and tone and meter. At least that’s how I start. Then I start crossing things out. Finding better words. Twisting and bending the meter until the poem starts to take shape. Then put it away for a few days. Reread it with fresh eyes and continue reworking it.
So basically, read up on the mechanics of poetry, read TONS of poetry, concentrate on how poets use imagery, rhythm, sound, tone, symbolism, etc… and apply that to your own ideas. Don’t get too crazy on symbolism, though. Everything in your poem needn’t stand for something. Some people approach poems as puzzles. Poems should not need to be approached as enigmas.
Oh, and to add to these scattered thoughts, write about what you know. My favorite (and my professor’s) favorite poems in college were ones I wrote simply about my neighborhood, life in the city, the ritual of baseball, etc. Subjects for poetry are everywhere. Give it good imagery, make it a bit personal, but universal enough to be enjoyed and understood by others. But speak in a voice which is comfortable and natural for you.
Easy, eh? 
(BTW, I wouldn’t necessarily characterize poetry as maximum emotion in minimum space. That is a part of it, but hardly the whole.)