I keep an old fashioned 3x5 card catalog of all the iris. This is in alphabetical order and contains description, hybridizer, date acquired and cost, awards and parentage.
I also keep a yearly combination notebook, bloom log and map on a clip board that I carry around during bloom season. Bloom dates and miscellaneous garden notes go in here as I work in the gardens. There is a separate photo log in this.
I have a basic spread sheet that just keeps track of name color and garden location.
Also try to keep an updated plant list here on ATP