ArticlesPlus, in conjunction with the Oxford Bibliography on Biblical Studies, both of which are on the Start Here page of this Guide, should cover most of the sources you're likely to need for finding journal articles on Old Testament studies.
Very often, especially for more recent articles, you'll be able to find them online fairly easily. If you can't find a link to an article, though, it doesn't mean we don't have it. See Getting the Full Text of Articles for what to do.
Very often, especially for more recent articles, you will find either full-text links or the icon right in the database itself. Unfortunately, there are many times when this doesn't happen.
The video below covers the situation when you have a citation, but not a direct link to the full text. If you are unable to view this video, try accessing it in YouTube
The video above covers the process of finding articles that are online.
On the other hand, though, there are many occasions when you don't have anything to click on to get the full text, such as:
Assuming you've identified your citation as an article citation (see this three-part video on identifying citations), you need to do a Periodical Title search in ALICE and search for the title of the entire journal, newspaper, or magazine—NOT the title of the article.
In many cases, especially for older issues, there may not be any online versions of the magazine, journal, or newspaper, but we may have the full text in print or microform. Below is an annotated sample screen of what you might find in ALICE for the non-electronic volumes of Newsweek.
These screens can be hard to interpret, so don't hesitate to ask for help if you get stuck!
If we don't have the article you need online, or in print or microform, you can almost always obtain it, for free, by making an Interlibrary Loan request.