where can i find new cassettes to buy?

moustly i want metal cassettes.

Ebay, thrift stores

Ebay and thrift stores are pretty much it for new metal bias cassette tapes. You can find some good deals on the yellow and black wrapper sony metal sr lately. I guess someone stumbled upon a warehouse filled with them. i haven't used this version of the sr, but the older versions are great. beware of tdk metals from after 1988. They suffer some sort of binder breakdown and will leave white residue on your heads and rollers, and can have dropouts too.