From what I read in the book the starting value of a skill is whatever the linked characteristic is. IE if Joey Nimble Knuckles has an Agility of 8 his starting martial arts skill is then an eight unless he pays character points to push it past what his stat value is. Is this correct or do you add skill and characteristic IE eight plus whatever the skills level is? So if his stat was eight and he paid the points for two levels(a massive 13 total points) is he then rolling 10 dice?
I will answer this question in even greater detail than needed so that in so doing I can address other potential questions before they arise.
To begin lets address what you asked specifically.
During the character creation process (when you have plenty of story points available to build your character) a player may buy the basic martial style for 8 character points.
This grants the character a ranking in the martial arts fighting style equal to his or her Agility.
In the example you presented above that would have been 8. So at this point the character would roll 8 dice to use his or her Martial Arts any time they desired.
Now, as you asked in the above statement let us say that the player wishes for his character to push the Martial Arts total to a number higher than the linked characteristic.
In this case the player would spend an additional 5 points for each additional dice he wanted to raise the Martial Arts skill.
What that means is if he or she wanted to raise the Martial Arts skill an additional 2 points it would cost 5 points for each of the additional points making the total as follows:
8 points for the original ranking + 5 points to raise it by 1 point + 5 points to raise it an additional 1 point (8+5+5+ 18 points total) which would then grant the character a total of 10 dice when using the martial style in question.
So not a massive 13 points but rather a considerable 18 points would be needed to allow the character to excel beyond the limits of the linked characteristic by 2. As you can see this is an expensive endeavor and as such is not often pursued by any except those who are fully committed to the concept of a characters' skill being greater than his or her physical attributes could normally support naturally.
Also there are rules for learning new skills with in the game itself located on page 148 of the Basic Compendium which should be considered by those who wish other options.
Now we could go a bit further in this direction if you have the Magic and Martial Arts Guide which provides expanded rules for both the Martial Arts and the Magic Rituals of the game as well as any and all skills which could be learned within a game.
But, if you have yet to acquire that book, I will choose to stop here so as to not confuse you by making references to rules which you have yet to be exposed.
However once you have the additional book The Magic and Martial Arts Guide I will be happy to delve further into the specifics of the process and explain how those rules are designed to further the plot and enhance the story-line of any adventure.
In addition to what Griffin indicates, there is an entire list of potential Skills in the book that each have their own initial purchase price (to get that base starting value as Griffin mentioned), plus a price to buy it up from that at a rate that could vary from 2 to 5 points for each point worth of increase, depending on whether what kind of Skill you're talking about. For instance, as Griffin mentioned, Martial Arts costs 8 point to initially purchase it (when making your character) plus 5 points for every 1 rank you increase it, while the cheapest Skills )such as Knowledge (Wit-based Skills), cost only 2 points to purchase, and merely one point per each level you wish to increase its Ranking.
Hopefully we answered your question. Just let us know if you have more!
Even though the cost is 8 I thought it would be the level of the linked characteristic? Mainly due to the idea of level caps and in the rules it stats that the starting value is X(x being the linked characteristic).
So if you only had a five agility it would be 5 to start(or depending on the martial arts out of the Martial arts/magic book it would be the linked X.