I've got a 1000' box of cat5e and one of cat6 (I hate the cat6, so hard to work with).
You can get them pretty cheap, like $50 a box. Much cheaper than paying $50 for a 100 foot belkin cable from compusa.
Also, the cat5 spec allows up to 100 meters (around 300ish feet) in a single run. So a hundred or two hundred or even three hundred feet will have no problems if you are carefull in the construction of the cable (dont untwist more than the spec of 1/2" for the ends)