Where is a reputable place/seller to get a replacement iPhone power adapter (the one with the green dot) instead of paying the rediculous amount Apple wants for one?
Assuming it's in need of replacement for some non-warranted reason (e.g. losing it ), you can just get any USB iPod charger ... eBay should be fine. It's just a 5VDC USB charging pin....
Don't know which iPhone you have but be aware some of them including the 3G S are not compatible with generic USB chargers. I have these Monoprice chargers and they work good with the 3G S.