For you non-US folks, LOPSA has a strong online virtual community; there is much more to LOPSA than the locals.  The locals are a great place to meet your fellow sysadmins in person, but you can also meet them online in #lopsa on Freenode (irc.lopsa.org).

And...  you might even discover (online) that there are enough sysadmins near you to start your own LOPSA local!