Billy has posted several tutorials on the Quilting Board which may answer many of your questions about cleaning your sewing machine. They are located the Tutorial link. (Go to Home then click on the Tutorial link).
Karen,
Here is the link to Part 1:
http://www.quiltingboard.com/t-45816-1.htm
Part 2:
http://www.quiltingboard.com/t-45983-1.htm
Part 3:
http://www.quiltingboard.com/t-46696-1.htm
It may seem a little intimidating at first but if you have any questions feel free to ask as many questions as you need.
The best advice offered to me was to take pictures as you disassemble your machine. The first machine I cleaned, I had a little challenge remembering which screw went in which hole. When I cleaned the 2nd machine, I decided to put the screw back on the machine immediately after taking off the part that needed cleaning. This made the task of putting things back together much easier.
Don't forget: We love looking at pictures :)