I am currently preaching-teaching a series on spiritual gifts based on the seven gifts listed in Romans 12:6-8. Elmer Towns says that these seven gifts plus the gifts of shepherding and evangelism are necessary for the building of the local church. I encourage my people to take Towns' online spiritual gift inventory.
When I first put together this sermon series years ago, I relied heavily on four resources: God's Children Gifted for Service by Charles Stanley, Motivational Gifts by Johnny Hunt, Connecting by Bill Hybels, and the book 19 Gifts of the Spirit by Lesslie Flynn.
As a young pastor, I was learning that "there is nothing new under the sun." It humored me when I listed to the Hunt series and realized that he had obviously listened to the Stanley series and just added some more!
I claim very little here that is original with me. Mainly a compilation of a lot of study from various resources. I hope they help someone!