There are numerous online sources for sermon illustrations or illustration ideas, but I thought I would tell my fellow elders or Bible teachers out there about a couple of my favorites.
First is the user-friendly, easy to search and navigate Sermon Illustrations section at Bible.org. This is just one of the helpful features that makes Bible.org one of the sites I frequent most when doing personal Bible Study or when preparing to teach.
Second is SID, the free Sermon & Illustration Database. Once you have downloaded the free software, you can then go to the David Holwick's Kerux Illustration and Sermon Database site to download some sermon/illustration sets. The database sets are updated periodically so that the list just keeps growing.
David Holwick has also provided a list of Questionable Sermon Illustrations, what he calls "illustrations that are too good to be true."
If you are like me and need a good source of input for sermon illustration ideas, I highly recommend these resources.