I just go to any site I can find and look at the way they do their sashes and borders and steal the ideas (LOL)
Here is one place to go to see how to do star sashing--keep looking around this site and you will get other ideas
http://www.quilterscache.com/H/Howtomakestarsash.html
I also sometimes go to hhtp://www.quiltville.com
check the quilts on the right side of the site and click on any of the free patterns and see what the sashing and borders look like. Then if you have questions about them ask them here. Some smart person will have an answer for you. I'm sure others will have more ideas for you.
I, too, am no expert, so I will watach this thread for more ideas.