You have not provided enough information to provide a thorough response. However, presuming that this is a residential remodeling job, the PA Home Improvement Consumer Protection Act applies. I would send a certified letter demanding the refund of your money. If it is not returned in short time, you should file a civil complaint and demand damages under the Act. You should also report the contractor to the PA Attorney General's Office right away!
Per Jason's answer, contact the PA Office of Attorney General to check whether this contractor is registered. You can get more information on the AG's website at www.attorneygeneral.gov/hiccon.aspx. If the contractor isn't registered, report him through the AG's Home Improvement Registration Hotline, at 1-888-520-6680.
Under the home improvement contractors law, your contractor may be guilty of fraud (which in your amount of under $2,000 would be a first-degree misdemeanor):
§ 517.8. Home improvement fraud
(a) Offense defined. -- A person commits the offense of home improvement fraud if, with intent to defraud or injure anyone or with knowledge that he is facilitating a fraud or injury to be perpetrated by anyone, the actor:
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(2) receives any advance payment for performing home improvement services or providing home improvement materials and fails to perform or provide such services or materials when specified in the contract taking into account any force majeure or unforeseen labor strike that would extend the time frame or unless extended by agreement with the owner and fails to return the payment received for such services or materials which were not provided by that date... .
In addition, he may be liable for triple the amount owed to you as a civil penalty under the Unfair Trade Practices and Consumer Protection Law.
If you let the contractor know that he is criminally liable for his failure to return your money, and that he would also be in jeopardy of losing his PA registration, perhaps he'll be more inclined to get your money back to you promptly.
Of course, as with all of my online answers, my advice is limited by the brevity of your question and the facts provided. Additional information would be required to provide definitive legal advice, so this answer isn't intended to, and does not, create an attorney-client relationship.
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