Your Sim needs access to a computer but first they need to Question another Sim. The Question option comes up while talking to another Sim although it may get denied if the relationship isn't good enough. I usually have my Sim talk to the other Sim until they become Friends and then select the Question option. Now, you need a computer. Click on the Computer, then under the Writing option should be the option to Write a Report on ... and a drop down box will give you the Sims you've interview recently. Select one of them and your Sim will sit down and write a report on them. Other ways to get information on Sims is to Rummage through garbage cans after dark.
Your Sim can also Review a restaurant by clicking on the Diner/Bistro, Review a game/concert at the Stadium, or Review a movie at the Theater. On the Computer this option is called Write a Review on ... under the Writing option.
Hope that helps.
