Just for clarification, I'm technically not an architecture student
yet; because of how the school works, I'm technically in Pre-Architecture, and I've not taken any classes that are different from anyone else in my school's design program. i.e. I've only taken classes on drawing, art history, and I'm currently in a "design representation" class (basically model building).
That being said, I've found a few good ways for finding inspiration, which applies to architecture and all other artistic fields. For example, tumblr! Tumblr is a great way to get a drip-feed of artistic things. Some blogs try to post stuff that fulfill some sort of specific aesthetic. Some blogs are devoted to a particular style of architecture. Some blogs are very general, and post anything related to a broad subject (architecture).
Flickr is also pretty good. People can create pools of photos (called groups) where anyone can submit their photos that meet some sort of criteria. Flickr is also good for just flooding your eyes with random things.
Save everything you find! Whether that means keeping a list of links to stuff you like, or actually downloading the content to your computer, just keep a record of stuff that you find interesting. And keep it organized, too! I split my reference photos into categories like nature, interiors, abstract, etc. You can even categorize your stuff by what you find interesting in it, like shapes, color schemes, patterns, etc.
Sometimes art can be found in really strange places too. For example, album covers. If you wanted, you could use a website that randomly picks music (i dont know of any), and look at the album covers. You could do the same with book covers, movie posters, etc.
One last recommendation: if you want to know more about what kind of art you find interesting, start trying to make some of your own! It doesn't have to be anything particularly interesting or complex. Just take a look at something you find interesting, try to discern how it was made, and see if you can replicate it!
Also, getting an education in something is a great way to learn more about it (duh!) If you want to learn more about art, take an art class! Sometimes that isn't possible, but you should take the option if it's available to you.
Now, onto the fun bit. Here's a giant dump of websites that I use for inspiration. Note that not all of this stuff is directly "hey look at this cool art! be inspired!!" but inspiration can be found in a lot of things.
Flickr - I love grain elevators
Logifaces
Visualizing Architecture - a website about architectural renderings
Wikipedia - Paul Rudolph
Projected Image Creator - makes an image out of triangles via an algorithm
Photos of old mining stuff - I used this a lot for my detail entry
Fulton Center Subway Hub
Machinery and computers of some kind
Timothy J. Reynolds - flat, low poly renders
Jeremy Mann - occasionally nsfw in the "Figures" section
Geometry Daily
Debris Maker
Donovan Valdes
The Daily Task - occasionally nsfw
Level Design Inspiration Machine
Paperholm
Imaginary Infrastructures
YHCNYP - glitch art
Videogame Art Styles
Architecture of Doom
Fuck Yeah Brutalism
Architags
CJWHO
Single Malt Mana
Paul Robertson
Shmorky
Fezzine
Tiny PMS Match
Emmy Cicierega
Liz Climo
Frenums - personal blog of an artist, so there's a lot of not-art stuff
Motion Addicts
Content Aware Typography
KC Green
Etall
Made In Hexels
A dead blog that took the name "Architecture" on tumblr
And just because I can, I threw together
a collection of album covers I think are cool.