By the way, a contract address is where the token is located. Its like a wallet address.
Is this what you mean?
1) You want a token but you can't find it on exchange
2) You will send the money/crypto instead of the token's contract address and have the equivalent of it to be sent to you automatically.
If yes, then that won't work. It's always a reminder to never send money to a contract address. Those you see wherein someone sending a token in a contract address is to execute the token swap for example and that's automatic. The one that transfers here is the token itself and not the actual money.
And out of curiosity, why bother purchasing this kind of tokens that isn't listed on the exchange? There is no liquidity so I doubt you will gain profit from it. You can also look at some decentralized exchange as it might have an active market there like for example Etherdelta for ERC20 tokens (if not listed, you can manually input it).
I guess, he is really a newbie when it comes to tokens. You can't send money to the contract address as goinmerry explained. Your money will be lost. Unless, the team gave that specific address where to send the payment like eth and in exchange they will give you the corresponding amount of their tokens to your eth address. But there will be instructions attached to it or form to be filled up. But if there is no prior agreement, I don't think what the OP is asking here is possible.
Or can the OP be more specific? So we know how to address your situation.