I am getting a new iPod Touch soon, and I heard something where you can install VOIP and use it as a phone by installing Skype. I have a couple questions:
1. With Voip, does it give me my own phone number on the touch where people can call me, even while just listening to music or while my touch is on but sitting at a desk or something?
Just to be clear, VoIP doesn't automatically imply a telephone number. In broad strokes, VoIP can refer to any service which allows live streaming voice conversations over the Internet. Some VoIP service providers such as Skype may go further and optionally provide a connection to the public telephone network as well.
2. How much do minutes cost?
Skype-to-Skype conversations that are purely Internet-based (ie not originating or terminating at a telephone terminal) are always free (excluding bandwidth charges by your ISP) -- Skype doesn't charge any subscription fee to sign up for the service, nor does it charge any per-use fee. (If you go through a 3rd-party proxy to connect to the Skype network, they may charge fees, but the fees are not coming from Skype itself.)
You can optionally link your Skype account to the SkypeOut service, an outgoing public telephone service, in which case you may choose to pay a flat monthly fee to place up to 10000 minutes of calls to telephones per month, or for occasional users you may prefer to choose a prepaid option with by-the-minute billing.
Additionally, you may link your Skype account to the SkypeIn service, in which case you are assigned an incoming public telephone number that others may use to reach you over the public telephone network - they'll be billed the same as they would be to call any other number within the assigned dialing prefix. You are not charged any per-minute rate for incoming calls (excluding your ISP's bandwidth charges) -- you just pay the subscription fee to hook up the number on a quarterly or yearly basis. Outgoing calls are handled through the terms of the SkypeOut service.
As previously mentioned, for any potential iPod touch application, incoming calls will only be accessable while the Skype application is actually running because the App Store doesn't currently permit 3rd-party applications which attempt to run in the background. Eventually, Apple's push notification service (still in development) may provide a workaround to this limitation.
3. I assume the mic and headphones from the new ipod earbuds work with the phone?
The new mic/headphone combo will work with any software written to run on the 2nd generation iPod touch.