There are a few books out there, to some extent it does depend on what sports you do. Obviously an endurance athlete needs different foods to a strength athlete.
For the strength athlete a non-veggie book, but it has veggie options is Power Eating.
From Human kinetics there is Vegetarian Sports nutrition
From Brendan Brazier The Thrive books
The vegetarian sports nutrition guide
A couple from Douglas Graham Nutrition & Athletic performance & 80-10-10
Bear in mind the last one's from Douglas Graham are high raw, low protein, low fat diets. Personally I've not found much success with athletes using that methodology, but I thought I throw in the options.
There are also things like Precision nutrition that have a useful plant-based eating section & on their forums have an actual vegan guy moderating the plant-based section who is actually pretty knowledgeable.
Hopefully that's been of some help to you? If you need anything more specific let me know & I'll dig about.