Are you thinking of creating an article on a band you know? First, check to see if there is already an article for the band. Next, remember that Wikipedia has certain music notability requirements that bands should meet in order to have their own article. Some of these include being featured in multiple non-trivial published works or winning a major music award, such as a Grammy, Juno or Mercury Music Award. A band need not meet all of these criteria, but it should meet at least one of them.