There are several options for filtering the courses within the Courses tab of Blackboard. The best way to find your current courses will be to choose the Courses I teach option under the Filters drop down menu in the Courses tab.
You can narrow the search down more by clicking the Terms menu drop down and choosing current term (or any other term you may be looking for).
There is also the search bar, where you can type in the course name, to find one course if you need.
Above you can see how the filters really help in narrowing down the courses shown on the page. This will make it much easier to find whichever course you may need to edit or answer messages for.