The mere fact that contracts are unsigned does not, of itself, mean the contracts are not enforceable. Obviously it will be more difficult for them to assert the contracts are binding if you did not sign them, but very often courts will find contracts to be binding if it appears a party, by its conduct, has effectively accepted the terms of a proposal.
For example, If you are sent a letter offering to sell you something based on the terms and contractual documentation attached and invited to sign the contract to confirm your acceptance, even if you fail to sign, if you pay the amount required under the contract a court is likely to accept that are indeed bound by the contract.
That said, if you have not actually done anything which indicates you both accepted a contract and were on notice of the offered terms (i.e. they can show you actually received a copy of the proposed contract before you acted in a way which indicated you accepted its terms) then even though the court may find there is a contract, it likely won't infer that the terms in their document necessarily apply to the contract.
I trust the above assists, but if you are still uncertain please elaborate on your circumstances so I can more specifically address your particular situation.
Otherwise, please rate my answer.