I need to send in my K-80 for its 25 hr. service, I realize I need to fill out a service request form on there web site. Is the service center in the U.S? What is the approximate cost of the service, barring it needing any major parts, and what's the general turn around time on the service, Thanks

Yes the service center is in Southern California. IIRC, the standard charge for the inspection minus any additional parts needed, is $300. Turn around time depends strictly on how busy he is but if he's not swamped, it's usually about a week.