If you are a student at a college or university, you can use your university library to access library databases. This can lead you to peer-reviewed journals. Some full text articles from their database can be retrieved online or you can get a manual copy of the article if the university subscribe to particular journals. Ask the librarian in the reference section about this.
You can use Google Scholar and put your topic and it should list peer reviewed journals. Also, use the advanced search in Google Scholar.
Use your local library website to access electronic resources. Some libraries have access to MasterFILE Premier and Info Trac OneFile,which has accessed journal articles. You can also talk to a librarian in the reference section about specific topic you are researching and possible ways to get a journal article you are looking for.