To do it right is not something that one can understand quickly. Not from a forum post, that's for sure.
I was in your shoes last year. What I did is just start racing on the track. Talk to a lot of people. Make friends from the track. You will learn a lot simply by being there.
I ended up getting a coach which is expensive, who required that I get not one, but two power meters which is REALLY expensive. But I can tell you that even though I have not raced yet this season, I am way faster. 6 months of committed sprint training will do amazing things.
To summarize though, I think you need to get to the gym and get used to doing squats, dead lifts, power cleans, and plyometrics like box jumps. On the bike, find a local hill and go as hard as you can for 1-3 minutes at a time. If you go 1 minute, try to get to a point further than the last time you did the same 1 minute effort. Each time. If you don't have a power meter, I think that is the best approach..
From a nutritional standpoint, end every hard workout with 30 grams of protein and plenty of carbs. Strive to consume a gram of protein in a day per lb of body weight, without consuming more than 30 grams per meal.
Ok there's my advice. Good luck!