Fashion is one of my biggest hobbies (no, I'm not gay) so I'll chime in. THIS MAYBE A BIT LONG SO BARE WITH ME:
I generally prefer European designers over American ones b/c the former tend to make clothes that actually FIT people and usually very well. Believe it or not, most Americans wear their clothes TOO BIG. The philosophy here is "comfort" vs actually looking good. Which is fine if that's what floats your boat.
If you want to look good and not like you bought an $89 suit from Target then listen up:
1) Try your BEST not to wear a solid black suit. If you do, that's totally fine as most other interviewees will be wearing their funeral suits as well. It's the path of least resistance for some reason. However, I'd recommend you go for charcoal grey suit instead (as someone else pointed out earlier). If you get stripes just make sure they're subtle stripes and not bling bling mafioso stripes!
When looking for suits, look at the back of the blazer and see what kind of vent it has. Most American suits make their suit blazers with what I call "The Butt Crack Vent" (aka single-vent). Those are fine but the European DOUBLE VENTS (one on each side of the blazer) looks 1000x better and is more functional. How you ask? B/c when you put your hands in your pockets the single (or even worse, no vent) blazer bunches up and looks very very akward.
It will be close to IMPOSSIBLE for you to find a double-vented suit at places like Brookes Brothers (American designer) and Men's Warehouse. I mean no insult to the poster that works there but most European designers blow the socks off American suit designers. If money is tight (which I expect since we're all students) I recommend you try out discount/outlet stores. Check out Nordstorm Rack, Off Saks, Filenes Basement, etc. You will often find an $800 European suit on sale for $200.
2) White shirt is fine, especially b/c interviews are during the day (stay away from wearing white shirts at evening events, unless you're wearing a tux!). A nice blue shirt is actually what I'd recommend. It would look GREAT with a nice yellow/gold, red, or even pink tie (it has to be the right shade of pink...subtle yet powerful).
Unless you're overweight (these shirts look best on slender people), I'd recommend you try to buy a shirt with a SPREAD COLLAR. Again, most European designers make nothing but spread collar shirts. What's the difference you ask? It allows more room to tie a full windsor knot with your tie giving you a more confident look! If you don't know how tie a full windsor knot, google it. There are TONS of websites that show you how. It's a piece of cake actually.
However, if money is not object (you lucky bastard), then go to your nearest Thomas Pink store and buy a nice white or light blue shirt for ~$150-$200. If you're trying to keep your cost down, again, check out the discount/outlet stores for nice spread collar shirts. Often you can get a $200 shirt for ~$40-$60. If they're FRENCH CUFF, even better. Just keep the cuff-links subtle to avoid looking like a baller on med school interviews. Just make sure the collars FITS you. Nothing looks worse than someone who looks like they're wearing their dad's dress shirt. Size 15.5 neck but they're wearing a 17.5!
3) The most simple rule when it comes to ties is to try to match your tie with your shirt and/or suit (as one of the poster eluded to above). I agree. You can't go wrong using that approach. However, don't underestimate the POWER of your tie. Don't be afraid to buy a really nice RED or GOLD tie. Show your confidence WITH confidence! This would especially look good with a nice light blue shirt. If you feel like you're trying to be like someone you're not then don't sweat it. Buy something more subtle that you're more comfortable with. Again, discount/outlet stores all the way for ties. Brookes Brothers, though, does have a very wide selection of ties. So there, I'm not all against American designers!
4) Shoes- 2 rules. #1) Don't wear the same cluncky shoes you wear with your denim. #2) Make sure they're clean and shiny. If you want a new pair, Aldo has some decent dress shoes for ~$80-$130. Of course there are some Italian designers but neither you nor I can probably afford them right now!
Remember, THIS IS JUST MY OPINION. Flip through some fashion magazines when you get a chance or look around when you're at the mall next time. You'll see many of the concepts I talked about.
G'luck bro!