I still havent raced the final boss although I have been told what the car is..... It sounds like you have beaten the first major boss and are about half way through the game.... You should find as you beat more gangs you will unlock more parts of the roads ( the last set are some long straight roads for good top speed runs ) ... some of the wanderers will only race you if you have some very specific things on your cars.... I won't even try to list them here as the list is pretty long, try going to www.gamefaqs.com and looking up the game as they have a list you can print out of every wanderer and what you need to race them.... I found that file incredibly valuable