I have no idea about them.Better Go to any local phone shop and ask what you want.They will give some ideas to you.
If you want to use other than Cingular sim card on your phone means,your phone should be unlocked one.If it's locked by specific network,you will need to unlock your phone.For unlocking you can approach your service provider or else try to buy an unlocking service from any one of the online unlocking service provider like Unlock-Zone.com Here you can unlock your phone at low cost.