I LOVE Rendaivu - Free Online Equestrian Management Software
It's a free online service that will keep up with all routine services and give you reports on what you're spending. It will also send out reminders if you set a "due date" for the next service. When entering a deworming record, I put a note when I schedule a due date as to which dewormer I want to use next.
You can enter in your horse's pedigree, photos, training records/schedule, show records/schedule, etc. It's very handy, no annoying ads or spam, and it's FREE!