Thanks wookie! It was fantastic, but exhausting! I had no idea how tired I'd be after 3.2 hrs flying.
At the risk of being on the receiving end of another stupid-stick I share the following:
These three full-stops at DSM were combined with my 150 NM XC requirement. The flight started off great: an on-time 8 AM departure with calm winds and a beautiful sky. I climbed into fairly strong winds aloft (for me!) of 35 knots @ 4,500 ft which were forecast and planned for. Heading calculations were pretty close so dead-reckoning was working as predicted and I saw all of my landmarks. Landed at my first airport about 60 NM away: Audubon, IA. The runway was a little difficult to spot being very close and parallel to the highway (and very narrow), but I was able to see it and performed a normal landing. It was the narrowest runway I've seen so I was a little anxious, but dare I say I greased it in

As soon as I landed I attempted to close my flight plan. Checking my cell I noticed there were zero bars for me at this dinky little airport just west of the middle of Iowa. I stopped the plane and went into the FBO to find exactly two working pieces of electrical equipment: a 1960's-style green CRT monitor serving as an automated airport weather station with some wires strewn about the floor, and a coffee maker. I located a phone's handset with one button on it hanging from a nail on the wall, but it had no sound and pressing the button had no effect. The other end of the phone was no where to be found. A note reminded visitors to please leave the computer turned on.
So here I am in a tiny airport with no phone and no means to contact anyone (I know, excuses excuses!) I saw no one in the vicinity so figured my best bet would be to take off for my second leg and call Ft. Dodge over VHF from altitude. I called them several times - 2,000 ft, 2,500 ft, 3,000 ft and never heard a response. I attempted to call traffic that I heard at nearby airports stating 'Guthrie traffic, this is a student pilot with request' to which I didn't hear any responses either. At this point I'm wondering if my radios are working because the radios in our training aircraft are pretty terrible, so if they failed it wouldn't have surprised me one bit. After trying Ft. Dodge one more time I figure I'm close enough to Des Moines approach that I can at least establish communication and ask them if I had the correct frequency for Ft. Dodge.
Des Moines approach responds to my second hail and gives me a transponder code and asks my altitude and position. I'm very relieved to be speaking to anyone! As I'm dialing in my transponder and describing my location and situation I hear Ft. Dodge on my other radio so I say to Des Moines that I'm going to switch back to FSS and will return to this frequency as soon as I am able. They approve the freq change and I get back to Ft. Dodge. I tell them my tail number and he pauses for a minute and says: "You're currently in search and rescue status. Would you like me to cancel that?"
This is not exactly how I wanted to start off my 150 NM solo XC. I'm feeling pretty ashamed then FSS says "I see you've got another flight plan from Audubon to Winterset. Would you like to open that now?" I look out the window to see the Winterset runway and politely decline the second flight plan.
The rest of the day's flying goes pretty smoothly. I completed a few of the most significant milestones for my private pilot's license and learned gobs of lessons along the way. First lesson learned: have a method to contact FSS if you're going to open a flight plan! I understand some pilots cancel the plan from the air as soon as the airport is in view. I may do that, but if the airport is abandon like this one appeared to be, there might not be anyone around to call 911 in the event of an accident on landing.
How do the rest of you handle closing your flight plans at tiny, remote airports where a phone might not be available?