You go to the same areas where you would enter your income. For example, to enter her W-2, go to the W-2 area. If you are filing a joint return, then when you first start the W-2 you will be asked to indicate whose W-2 you are working on, yours or your spouse.
The same is true for other types of income when filing a joint return. If it is important to make a distinction, the program will ask whose income you are entering.