Q. How do I do an in text citation APA style with one or more authors?

When your in text citation is not a direct quote, all that is required is a reference to the author and year of publication. Very simple when there is just one author. If there are more you do different things based on the number:

Examples:

• One Author
  Though most teens belong to at least one social site, there is very little peer reviewed research on the topic (Thompson, 2012). 
• Two Authors
  Though most teens belong to at least one social site, there is very little peer reviewed research on the topic (Thompson & Gragan, 2012).
• Three to Five Authors
  List all the authors within the text of your sentence or in parentheses the first time you cite the source. Use the word "and" between the authors' names within the text and use the ampersand in the parentheses. In subsequent citations, only use the first author's last name followed by "et al." within your sentence or in parentheses.
  

Though most teens belong to at least one social site, there is very little peer reviewed research on the topic (Thompson, Gragan, & Perry, 2012).

• Six or More Authors
  Though most teens belong to at least one social site, there is very little peer reviewed research on the topic (Thompson et al., 2012).