I was arrested and my Miranda rights weren't read. Can that help me?

Miranda only applies, as the previous person said, if you are in custody and then questioned and make statements that could be used against you.  If you are in custody and not questioned, then they don't need to read you your Miranda rights.  If you are not in custody, and questioned, and you say stuff, it's admissible because Miranda only applies to "custodial interrogations."  And if you are in custody, and questioned, and you say stuff like "I'm completely innocent" then I suppose Miranda would apply, but who cares?  You've simply made a statement about your innocence.

Also if you are in custody, read your rights, refuse to speak to the police, but you subsequently make "spontaneous utterances" (which are unprovoked statements) those can be used against you, so long as the cops didn't induce the utterances.

Many people believe that they can "beat the case" if the officer doesn't read them their Miranda rights during an arrest. This is a myth.

Basically, the Miranda warning must only be given if a person is in custody and then questioned.  Any questioning before being taken into custody is legal.  However, if a person is in fact in custody and then questioned without being Mirandized, then any statements so made cannot be used.  The two exceptions to this: the statements were voluntarily and knowingly made any way (ie the defendant waived his rights); or the questioning incidental to the booking process (ie. name, address, etc).