I didn't buy a training plan, I entered Eroica as an event with 8h of riding and 100 mi distance and the estimated CTL based on the last century I did. I then created a ATP(annual training plan) including the event and TP gave me the weekly training load and ramp rate I would have to do to build up to Eroica. As far as workouts there are lots of workouts to do all over the web, personally I use Zwift for the workouts and as long as I stay on track and continue to ramp up on schedule I should be OK. If you are looking for a workout plan Trainer Road has a free month trial if you can find a code or sign up for Zwift and use a workout plan there. From what I can tell Zwift and TrainerRoad have no way to put a plan together for a specific event like TP but the workouts are good.