Hello, my radio has been locked and I was never given a code on how to unlock it, I bought my car second hand and I accidentally locked it the other day when fixing the gps, what can I do or where can I get a radio unlock code 

It should be coded to the car and unlock if you switch the ignition on with the radio off and then turn the radio on.

What model radio is it?

It's a culumbus 

For skoda, https://www.radiocodeking.co.uk/skoda-radio-codes can provide those radio codes for free. I am not affiliated with them but I was so amazed how they get those codes for us for free of charge. Make sure you put the code:freeforall on their checkout page to avail their promo.