+1 for linux-author's advice. You can get used tires and tools on e-Bay. Free instruction on how to do maintenance is available to anybody with internet access at Park Tool's website. Were I in your shoes, I'd buy a basic tool kit - do the tune-up via internet coaching - and keep the remainder of the $50 in reserve for a set of used tires (if and only if you need them) later on.

Go enjoy the hotties on the bike path! The motto for a happy marriage is "It doesn't matter where you get your appetite, so long as you eat at home!"