I just changed mine this past weekend. I picked up an oil filter wrench like this one:
Pennzoil 19902 - Filter Wrench | O'Reilly Auto Parts
at Oriellys auto parts for 6 bucks. Without it, I could not have gotten the little bugger out of there. Absolutely NO room to work with in there. Went 6740 miles before it told me to change the oil.
Good tip, I doubt there is any real DIY or anything on how to change the Chevy Spark's oil yourself, although it's an easy process to some of us, to newbs it's not.
What oil filter did you buy? and what brand and grade of oil did you use?