You can assign any picture to use for a contact, regardless of whether they've chosen one. This picture selection only appears in your Gmail interface; your contact won't see it unless you suggest it for them.
- Sign in to Gmail at mail.google.com.
- Click Contacts.
- Click on your contact's name in either of the Frequently Mailed or All Contacts lists.
- Click edit contact information.
- From the Picture section, select the My pick radio button and click upload picture.
- In the pop-up window that appears, click Browse.
- Navigate to your desired file, making sure that it's a JPG, BMP, GIF, or PNG file, and click Open.
- Click Upload picture.
- Depending on its dimensions, you may be asked to crop your picture to fit into our size restraints. Use your mouse to drag the selection box, and click and drag on any corner of the selection box to shrink or enlarge it.
- Click Crop picture. Don't worry -- any changes you've made won't affect your original file. They'll only appear in Gmail.
- Click Save to assign this picture to your contact.