newbie need advise

am 44 getting ready to go to school oct9th taking a 15 week course for my cdl-a and Endorsements the course is ptdi certifed total of 600 hours of training to include actual otr training .trying to get some info on get a prehire before graudation in jan 2010.have alittle problem possible two.
have not work since june 05 do to injury collecting ssi and for a short time in that period was taking care of my ill mother.now released and cleared by doc to work with no limitations,but also so have misdemeanor conviction in 2000 for 2nd deg assualt,handgun on person it was mine and registered just not stored properly.also volation of probation all in 2000.all is finished has been since 2003.no charges since or prior to those.
how hard is going to be for me to get with a decent company so can earn a living and run some miles.any help suggestions or advise very much appreciated.a list of possible company to look into would be great.no dui or accidents ever reg license since 16 now 44 no points or tickets of any kind.and prior to my none work related injury had a great work history. thanks an advance