I plan on making chili or something similar.
In the four or five previous events I've hosted I have asked people to bring their own beer/wine etc. along with a desert/snack to share.
Of course equipment is expected along with software (records, cds, etc.). I usually appoint someone to make sure that we get to hear them all. I've got a fair amount of equipment here and with my two-story garage, I have two locations for systems there along with two more in my tiny cabin next door.
Looking forward to it and more info will be provided later.