What 'type' of lawyer would I need to contact if I'm having trouble with a retail employer?

I know there are lawyers for different types of cases and work environments. I'm being accused by my current job of something I didn't do (they're saying I used a coworker's sales number 'in between mine' on one single night a couple of weeks ago). I've been with the company for nearly 2 years. I have quite a few doented emails regarding our constant connection problems with the registers, which go up an down frequently on a daily basis. When that happens, we've had all sorts of crazy and off the wall stuff happen that I didn't think a register could do - but all of us at the store have experienced it. I'm being blamed for something that I feel is a computer error. The Loss Prevention Director of the company has made a few 'threats' but so far all that he has is a video of me in front of the register at the alleged time and a "list of transactions" from the time. My sales number, however, appears on a ton of sales that night. The coworker's number in question only showed up what looks to be around 2-3 hours, and they weren't even there during that time. My number continued on ringing sales. I'm looking for another job, because the whole is a disaster and one of the managers has been making up complete lies about me trying to "get me into trouble" with the loss prevent by saying off the wall stuff like his most recent lie: he told the store manager that I said to him that the "company would pay for me lawyer fees." I don't have a lawyer as of yet; I informed the loss prevention director of that when I was questioned about it, and he said that these two workers have "given statements" about me. However, the two workers are actually one - the t. manager told the store manager a lie of gossip and she believed him, so the loss prevention guy somehow considers her a "second statement." Again, with no proof of either. This t. manager has said derogatory things about me to many employees past and present, and one time was very racist against me. He told another employee (who no longer works there, of course) and that employee told me. I informed my store manager of it and nobody did anything about his comments. He doesn't like me because he apparently is scared that I might take his job. What kind of lawyer can I get for this, if any? What's my best option? I basically want to leave this company as soon as I find another job. I do not want any 'trail' following me to cause any trouble once I am working another job. This company is in violation of OSHA standards for bathroom breaks for employees working up to 8+ hours alone with no help or coverage, yet they cannot close the store at all due to policy. The computer equipment at our stores is SO bad that employees are frustrated to come to work daily because we have to do a lot of "manual transactions" because credit cards won't swipe due to the system connection issues. When the connection goes down and comes back up, drawers mysteriously come up over/short of cash due to transactions that didn't process properly. I'm concerned that this system is kicking out a lot of errors; do I have a defense against these allegations? If so, what?