I would also just try to find a used saddle. I got a beat up selle flite for $5, as long as you don't mind some wear and tear good comfortable saddles can be had for cheap now and then.
Tires on the other hand are not cheap. Well, cheap tires are, but I hate cheap tires. Vittoria rubino pros are pretty much the cheapest tires I would want to pay money for, but like saddles, you might be able to get a good deal on some take-offs if your LBS does that (the one here sells take-off saddles in a box and sometimes has tires).