I recently "released" (he says in quotes because it's still sub-alpha, albeit functional) PigIron 0.3 Java Class Library for IBM VM SMAPI. I blogged previously about PigIron. Working on PigIron has made me refresh my view of mainframe programming resources.
While mainframes as a corporate database backbone are in retreat over the long term (somewhat like Tolkien's Elves slowly fading and setting sail from the Grey Havens), mainframes themselves continue to flourish and grow in usage slightly, especially as farms for multiple virtual instances of the GNU Linux operating system.Pam Derringer's article on U Ark's computer engineering program, SUSE-Linux-on-IBM-loaned mainframe becomes teaching ground is interesting in this regard.
Links like the trail of a hound dog following his nose through the z/VM culture are found on my IBM z/Series ® Mainframe Programming Page.
Mainframe programming mailing lists run on a piece of software called LISTSERV and there are several somewhat co-ordinated LISTSERV sites such as: