Don't feel bad, I've been riding for almost 20 years (good God that makes me sound old) and I still don't have proper rain gear. It may just be that I don't mind riding in the rain
Stuff to keep on hand at the house (at least I've always had this stuff):
chain lube
WD40 (for use when cleaning the chain)
engine oil
coolant
some shop rags (for cleaning the chain)
an inexpensive rear stand (makes cleaning the chain a lot easier)