As has been suggested above, the US authorities have no direct access to UK criminal records. (EU privacy laws are meant to prevent such information being passed on). However it's almost certain that a great deal of information is passed on under the guise of 'preventing terrorism' (even when that information doesn't actually relate to terrorists activities). So you'd be extremely unwise to try to enter the USA with an ESTA.
US law automatically bars anyone who has ever been convicted of an offence of 'moral turpitude' (which includes theft) from entering their country. So, in the first instance, the US Embassy would have no alternative but to refuse you a visa. However your request could then be referred to Washington as an application for a 'waiver of permanent ineligibility'. The process is extremely long, with a minimum wait of around 5 months from the start of the application process. (The longest wait I've seen reported on this site was one of 15 months from someone with two convictions for driving without insurance. His application was refused). So you need to start your application NOW! See here:
http://london.usembassy.gov/niv/add_crime.html
While the US authorities don't recognise the UK's Rehabilitation of Offenders Act, the passage of time will almost certainly be an important factor in any decision. (I've read of people being told that they needed to wait 10 years from the end of a sentence in order to stand a chance of acceptance). So there's probably quite a good chance of you eventually getting a visa as long as you act PROMPTLY.