The Sony Ericsson Spiro really has no bells and no whistles when it comes to this part of the phone. That's not to say it's bad, but a socially integrated phone this ain't (though it can be done with this kind of phone, as the Nokia C5 proved).
The simplest way to access your contacts is by using the right-hand softkey from the Home screen. It simply takes you to your contact list, with the 'New contact' option at the top.
When adding a new contact, you start with their name, and a number (you can specify home, mobile and so on). By moving across the tabs on the screen, you can also add email addresses, pictures and custom ringtones, addresses and the contact's birthday.
Within the contacts list, you can simply scroll to a name to see its primary phone number. From there, you can hit the green Call button to ring them, or press the central key on the navigation pad to open the contact and see all its details.
From there, you get context-sensitive options for each bit of information (when on phone numbers, you get the option to send a message – to call you still need to use the green Call button).
While the Spiro had no problems getting and keeping a good signal (in fact, it was better at finding an Edge signal than many smartphones), call quality was actually a little disappointing.
Calling a landline was okay, but calling another mobile could often lead to great chunks of conversations becoming garbled. The speaker is also quite easily drowned out, so trying to hear someone when they were near a road was often very difficult.