To add an Information Link to an existing analysis in Spotfire version 7.14 and lower, one had to click "File" > "Add Data Tables" > choose "Information Link" from "Add" dropdown button.

This has changed in versions starting Spotfire version 10.0. 

Changes in Spotfire version 10.0 and higher : How to add an Information link to an existing analysis?

In the latest versions of Spotfire (10.0 and higher), users have to follow the below steps to bring data into Spotfire through Information Link:

1) Click on the "+" symbol for "Files and data" flyout.
2) In "Files and data" flyout, choose "Browse the library".
3) Navigate to the folder in Library where the Information Link exists.
4) Click on the Information Link which will open the Summary View.
5) In the Summary View you will see the Information link which you are trying to add.
6) Click on the Information Link which will open other settings options.
7) Choose "Add as a new data table" from the settings and click "Ok" button.

The below gif demonstrates the above steps.