Been going to Amsterdam since 1990.
The Flying Pig is a pretty well-known hostel (community dorm) type place...inexpensive and all. 2 downtown locations, I believe. Never stayed there, but I've been by it. It's known to be a friendly, crowded, social environment - mostly college kids like yourself.
I've never done shrooms in A'dam, just weed and hash. I've been to the smartshops though: SmartZone, Innerspace and Conscious Dreams are some 'name' places for shrooms.
There are a lot of places to get good weed/hash. Bluebird is known for its wide range of good quality hash. Barney's, Katsu, de Dampring, Grey Area, de Rokerij, Dolphins, Tweede Kamer are some places with good reputations for top weed, although there are many more excellent coffeeshops to be sure. Contrary to what the good poster above said, the Bulldog is not a very reliable place for good gear. Most people who want good gear stay away from this tourist trap.
Part of the fun of going to A'dam is planning it all out. Another is knowing what gear is appropriate for what activity. For example, you don't want a weed that's going to lock you to the couch if you plan to do a lot of daytime - sight-seeing - social stuff. Pot comes in 2 strains: Sativa strain = "up", energetic, get-stuff-done, museum hopping, sightseeing high. Indica strain = "stone", heavy, late-night, gaze-at-the-wall-for-hours, listen to music, chill-out high. Tell the clerk what your looking for. Hash/Ice Hash is concentrated THC, and some of it is just amazing. I'm partial to hash myself.
As I said, half the fun is planning the trip...
Feel free to pm.