Where would I go for a copy of a contract?

My company contracts with the state and recently signed a new contract with them (about a year ago). I have heard that the new contract gives a wage amount which I and my coworkers are not being paid (rumor is we're being paid well under contract requirement). I want to see the contract for myself and see how much we're being underpaid and if there are grounds for a class action lawsuit (which I've been told there is, but I want to do the research myself). I know the contract is public knowledge and I'll have to pay a fee to get a copy, but I don't know where to go to get the contract. Is it the court house or another agency? I live in Boise, Idaho if that helps. Thanks much in advance!