If you are having trouble getting into your OmniBazaar account, it almost certainly means that either the username or password are incorrect. You must enter BOTH the username and password exactly as you did when you signed up. Remember, user names contain ONLY lower case letters and numbers. Check the CAPS LOCK on your keyboard.
The OmniBazaar wallet work in a way that is very similar to other cryptocurrencies. As long as you have the “brain-key” or private key for the wallet, you can access the contents of the wallet from any machine. In the case of OmniBazaar wallet, the combination of your username and password acts as the private key to your account. This system allows you to access your account from any machine that has OmniBazaar installed, as long as you provide the correct username and password. The combination of your username and password generates the required keys each time you log in. But, those keys do not get stored on the local machine. So, there is no place on your local machine to "find" or "recover" them.
Unfortunately, there is no way we can help you recover a lost password.
If you created Bitcoin and Ether wallets within OmniBazaar, you were given a chance to save the access information for those wallets. As long as you saved the account access information in a safe place, you will always have access to those wallets from any machine.
I hope you will be able to remember your correct username and password. That is the only hope you have.