take a look at danny eslick. seems like he just popped up but he's been at this for many years. or josh herrin... 16 yrs old, out there giving the veterans a run for their money. and he just got a factory ride. jeesh.
also you have to think like this: http://www.superbikeplanet.com/2006/Oct/061019b.htm
you need to be fast and you need to have a **** load of income ie; need to be able to afford several bikes, parts for both bikes, a tech to work on them because as a racer the last thing you want to do is worry about your bike when you come in from practice or qualafying and have to work on your own bike and then go back out for another session plus its hard to do your own work when you have to run around to racers meetings and such. traveling with all of this equipment isnt cheap either. tires will run you inexcess of $400+ per race (unless you doing eight lap sprint races which aint **** if you want to go pro) the list goes on but good luck.
"racers meetings" are once in the morning and dont' require a lot of running around.
also, spies started out doing regional "eight lap sprints" on a single set of tires a day. he also used to run a longer format race that was, i believe, 16 laps. in the longer race, he used to beat guys on "big bikes" with his 250gp bike (or was it his 125... i can't remember).
by the time he turned 16, ben had been noticed for quite some time and john ulrich hooked him up with a gsx-r600 to clubrace with until he was old enough to race AMA. the rest, well, you've seen on TV.
if you have the talent, you just have to make sure you get noticed. that doesn't mean spend crazy money on A and B bike, and a transporter, a top mechanic and all that. the assistance will usually come with time. there are people at the track that love to cultivate talent. everybody wants to find the next lawson, rainey, spencer, shwantz, edwards, spies, and kozinski.
but you DO have to get noticed. that usually means local competitiveness , competitiveness at the wera GNF on the east coast, competitiveness at the WSMC local races, or WSMC's one off "Toyota 200". there are other orgs and regions, but WERA is the largest and WSMC is the closest to the US headquarters for all the Japanese motorcycle manufacturers... it's motorcycle country.