To second what folks above have said, buying a pre-made temperature controller and a fridge/freezer/etc will definitely get the job done. You're going to need some kind of an external temperature controller, since very few fridges or freezers are going to have built in settings to maintain anything much higher than 30'sF.
However, if you're a little handy and enjoy tinkering, do some searches on this site for the ebay temperature controller - I built mine for around $50, which is a LOT cheaper than I could find a pre-made 2 stage (heating and cooling) temperature controller. Also, search for threads on fermentation chambers - like mine
</shameless plug>. They can be as simple as an extension of a dorm fridge built from rigid styrofoam insulation or small rooms with modified air conditioning units attached. Mine falls somewhere between those two extremes, and is currently happily fermenting away 10 gallons of a bock at 10C (about 50F).