I'm sure I'm going to feel stupid after I hear the answer, but how do I save the addresses I've entered on my phone over to my SIM card?

You can't save the address. You can save one phone number per SIM card contact... go to Address Book, click and scroll down to SIM Phone Book. Click, New.

One name, one phone per item.

highlight the entry that you want to copy to the sim card> click trackwheel> view> click trackwheel again> copy to sim.

Must be done one at a time