Here is a general 12 week training plan for starting pentathlon. It is definitely better to find a coach (or group of coaches) to plan and oversee your training, but not everyone has that opportunity, so I put this plan together. Feel free to adapt it to your needs (for instance, experienced riders need no more than a ride per week, while those who have never ridden will not be prepared to ride in 12 weeks, so they might as well skip that event for this year), or even send me feedback/additional plans.
Davis Pentathlon 