Can't install any packages in Node.js using "npm install"

I'm new to Node.js, and I'm going through a few tutorials. For some reason, I can't install any new node modules.

I am using: Mac OSX 10.7.4, Node v. 0.8.6, NPM v. 1.1.48.

I run npm install X and I always get a

npm ERR! fetch failed https://registry.npmjs.org/-/X
npm ERR! Error: 404 Not Found

When I actually go to the npmjs registry, I can see the project page, but no matter which tarball link I hit, it's always the same:

{
    "error": "not_found",
    "reason": "document not found"
}

For example, I tried installing fs by running npm install fs and I get:

npm http GET https://registry.npmjs.org/fs
npm http 200 https://registry.npmjs.org/fs
npm http GET https://registry.npmjs.org/-/fs-0.0.0.tgz
npm http 404 https://registry.npmjs.org/-/fs-0.0.0.tgz
npm ERR! fetch failed https://registry.npmjs.org/-/fs-0.0.0.tgz
npm ERR! Error: 404 Not Found
npm ERR!     at null.<anonymous> (/usr/local/lib/node_modules/npm/lib/utils/fetch.js:47:16)
npm ERR!     at EventEmitter.emit (events.js:115:20)
npm ERR!     at WriteStream.flush (fs.js:1514:12)
npm ERR!     at fs.close (/usr/local/lib/node_modules/npm/node_modules/graceful-fs/graceful-fs.js:92:5)
npm ERR!     at Object.oncomplete (fs.js:297:15)
npm ERR! If you need help, you may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>

npm ERR! System Darwin 11.4.0
npm ERR! command "node" "/usr/local/bin/npm" "install" "fs"
npm ERR! cwd /Users/comocomo/Documents/workspace/nodeTest
npm ERR! node -v v0.8.6
npm ERR! npm -v 1.1.48
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /Users/comocomo/Documents/workspace/nodeTest/npm-debug.log
npm ERR! not ok code 0

I tried fs, fs-extra, express, and formidable, all giving me the same 404 response. There must be something wrong on my part, I'm pretty sure the whole registry is not broken.

Am I using an old registry? Should I change it in my config file? I honestly would rather not start installing things manually, and I'm sure it's just a small configuration issue.

Thanks!