To view an individual grade: click the Assignment link in the top menu bar. Then click on the name of the Assignment/Discussion/Final Project. Here, you can see the overall grade, the rubric values used to assign the overall grade, and the feedback.
To view a list of all grades: go to the Administration menu (look for the Tech Support question about restoring these menus, if you do not see them in the upper-left of your screen), and click on Grades, under Course Administration. This will display a list of all of your current grades in the course, with their corresponding feedback.
Please note that the category grades and the overall course grade that are listed here, are calculated based on the grades that are already assigned, and do not take into account grades that have not been entered.