Get as many as possible. (I know of someone who had over 40!). Ask the people writing them to send them to your solicitor. He/she will decide whether to just put forward the 'strongest' two or three, or to submit the whole lot to the court.
A court would probably give less weight (if any at all) to a character reference from a family member (or girlfriend) than they would to one from, say, an employer. (Your employer might have only known you for 6 months but that's plenty of time for him/her to recognise that you're a reliable and trustworthy employee). However, there's nothing to prevent a relative or girlfriend from writing a character reference for you. (Just leave it up to your solicitor to decide whether it's worth putting before the court).
It's entirely up to the people writing the character references as to what they write but here's a rough draft for you:
"To whom it may concern, in the matter of Regina v John User1:
I have known John User1 since he entered into my employment in January 2008. During this period he has been an exemplary employee. He has always been punctual, reliable, honest and trustworthy.
Further, he has related well to other staff, as well as the members of the public with whom he has come into contact.
The matters which bring John User1 before the court are totally out of character for him. I know that he feels genuinely ashamed of his actions and I am confident that he will not reoffend.
Yours respectfully,
A Employer"
As I stated previously, get as many references as possible. Some magistrates or judges might be impressed by the professional qualifications of the people providing the references; others might not. However, if you know any teachers or lecturers who've taught you over the past few years, it might be asking them for a character reference.
Chris