CPA's just as other professions have the good and the bad. So what should you do if you have an experience that is not too professional? CPA's are licenced Certified Public Accountants who have passed a rigous test and met state guidlines of experience and education to work for the public. I am not a CPA, yet, but CPA's are supposed to work in a way that does not harm their client. With that said that does not mean they make mistakes that can be costly to you or your business.
As an accountant I can do everything a CPA can I just can't put a seal of approval on it. Sort of like contractors you have bonded and licenced ones and those that are not. The ones that are not bonded and licenced can still do everything but you take a risk with them. I can produce financial statements but they can only be for your eyes only a cpa can certify them and then they will be able to be used for financing (such as getting a bank loan, or money from a venture capitalist or SBA). I said all that to tell you to take my advise as that. I am a professional but I am not a certified professional.
The first step to find out about any CPA you hire is through your states board of accountancy. Every state has them and every CPA has to be licensed. Most states have an online tool that allows you to search not only the credentials of your CPA but also their displinary history. If you state doesn't have one call up your state board and inquire them about your CPA they should be able to give you the information. This board is also your fist step in handeling a CPA that did you wrong. Trust me if they are getting a call from the board of accountancy (the one that holds their licence and their ability to practice) they will try their best to correct the problem.
Another step you can take when hiring a CPA is to find out what extra affiliations they have such as a membership with the aicpa, or their state cpa society. These affiliations require them to have a much higher duty of care and they are subjected to peer reviews. I am a member of my state cpa society (because I am a cpa candidate) and it is a great affiliation to have. You also have another place to file a complaint. Though I am not a cpa if I mess up someone could conceivably file complaints against me with the cpa society and once I pass the test I would not be able to be certified. Complaints against cpa's and candidates are taken very seriously so use them as a final resort. If you threaten your cpa with a complaint if they value their career they will straighten up real quick.