I have tried just about everything...how can I get rid of cockroaches!!!!!?

my husband & I are the cleanest people in the world, but I brought in a stereo that was given to me which had roaches, & I haven't been able to get rid of them since!!! I have bombed...srayed..tried borax bait...you name it!!! They go down to a dull roar, then the re-surge...HELP!!!