Ember Not Initializing Store Properly: Cannot read property 'find' of undefined

All my versions:

Ember: 1.9.0
Handlebars: 2.0.0
jQuery: 2.1.3
Ember Data: 1.0.0-beta.12

All I'm trying to do is make a simple Ember Data store.find() call and everything seems to be going horribly wrong. It gets even weirder too. If I wrap this.store.find(...) in a get() call and instead say this.get('store').find(...) I get a completely different error.

Here's the error I'm getting with just this.store.find(...):

Error while processing route: budget Cannot read property 'find' of undefined TypeError: Cannot read property 'find' of undefined
at Application.BudgetRoute.Ember.Route.extend.model (http://localhost/javascript/app/routes/budget.route.js:9:24)
at EmberObject.extend.deserialize (http://localhost/javascript/bower_components/ember/ember.js:24849:21)
at applyHook (http://localhost/javascript/bower_components/ember/ember.js:47575:30)
at Object.HandlerInfo.runSharedModelHook (http://localhost/javascript/bower_components/ember/ember.js:45596:22)
at Object.subclass.getModel (http://localhost/javascript/bower_components/ember/ember.js:45822:21)
at __exports__.bind (http://localhost/javascript/bower_components/ember/ember.js:47449:19)
at tryCatch (http://localhost/javascript/bower_components/ember/ember.js:47898:16)
at invokeCallback (http://localhost/javascript/bower_components/ember/ember.js:47910:17)
at publish (http://localhost/javascript/bower_components/ember/ember.js:47881:11)
at http://localhost/javascript/bower_components/ember/ember.js:29453:9

this.store is undefined here.

Here's the error I'm getting with this.get('store').find(...):

Error while processing route: budget Assertion Failed: Budget has no method `find`. Error: Assertion Failed: Budget has no method `find`.
    at new Error (native)
    at Error.EmberError (http://localhost/javascript/bower_components/ember/ember.js:13740:23)
    at Object.Ember.assert (http://localhost/javascript/bower_components/ember/ember.js:3902:15)
    at Object.EmberObject.extend.store.computed.find (http://localhost/javascript/bower_components/ember/ember.js:24892:19)
    at Application.BudgetRoute.Ember.Route.extend.model (http://localhost/javascript/app/routes/budget.route.js:9:32)
    at EmberObject.extend.deserialize (http://localhost/javascript/bower_components/ember/ember.js:24849:21)
    at applyHook (http://localhost/javascript/bower_components/ember/ember.js:47575:30)
    at Object.HandlerInfo.runSharedModelHook (http://localhost/javascript/bower_components/ember/ember.js:45596:22)
    at Object.subclass.getModel (http://localhost/javascript/bower_components/ember/ember.js:45822:21)
    at __exports__.bind (http://localhost/javascript/bower_components/ember/ember.js:47449:19)

This time it finds this.store, but the Budget model has no find() method on it (and no where on the internet are there instructions that say there should be...)

budget.route.js:

define([
  'ember',
  'application',
  'controllers/budget.controller',
  'views/budget.view'
], function(Ember, Application) {
  Application.BudgetRoute = Ember.Route.extend({
    model: function(params) {
      return this.store.find('budget', params.budget_key);
    }
  });

  return Application.BudgetRoute;
});

My Budget model:

define([
  'ember-data',
  'application'
], function(DS, Application) {
  Application.Budget = DS.Model.extend({
    budget_key: DS.attr(),
    user: DS.attr(),
    title: DS.attr(),
    description: DS.attr(),
    picture: DS.attr(),
    order: DS.attr(),
    created: DS.attr()
  });

  return Application.Budget;
});

My ApplicationAdapter:

define([
  'ember-data',
  'application',
  'models/budget'
], function(DS, Application) {
  Application.ApplicationAdapter = DS.RESTAdapter.extend({
    namespace: 'api'
  });

  return Application.ApplicationAdapter;
});

I'm also using deferReadiness() and advanceReadiness() if that makes any difference here...