http://www.986faq.com/7-0/schedule.asp
prices vary, an oil change will cost a diy'er about $50, the dealerships often charge $150-200 (but also include some other visual inspections/topping off), and independent mechanic will charge somewhere in between. Your local dealer should give you phone quotes for specific services, if you call and ask. But, sometimes even different dealers have different prices for a particular maintenance service.
HTH,
Larez2