Fiancé/spouse visa

Hi.

I am looking for some advice regarding applying for a fiancé/spouse visa.

I am engaged to my fiancé, who is an American citizen. We have discussed the option of me moving to the USA to start our married life and starting our own family.

I have a major/impossible obstacle to get over and am looking for any valuable advise?

I have a criminal record for fraud. I was sentenced to 3 years in prison in November 2012. Due to good behaviour, the majority of my sentence was completed in an open prison, given home visits etc.  I was released on good behaviour in January 2014. Completed my probation, got a good job on my release and have since purchased my own home. 

I'm aware this is an extremely serious crime, and that it may be of no hope applying.

This is the only time I have ever been in trouble (I understand that this probably won't even matter)

We are looking to hire an immigration attorney, but would welcome any advice.