Hi!

I assume you are looking for a cutter like this: YouTube - Diamond wire sawing or YouTube - Diamond wire sawing

what material are you gona cut? concrtete, metal? you can get diamond wires for any material, but THIS WIRE COST BIG BUCKS! i would guess in $ somewhere between 150 -350$/ metre (approx 3 ft), you need atleast 10 metres to get started, depending on the saw.

the saw itself cost about 40000-70000$ (good guess:D)
but man it is a great tool when you can use it! but i really recomend that you hire a skilled opertator, the wire turns about 26m/s, so it is really easy to do deadly damage when the wire breaks!
and it can be a pain in the .ss if you don't know how to set up the wire right

some manufacturers:
Husqvarna Construction Products Welcome to Husqvarna Construction <-- i would recomend these guys!
hilti.com
TYROLIT Global - TYROLIT Group - TYROLIT is a leading supplier for innovative solutions in grinding, cutting, drilling, honing, dressing and polishing. <-- they have a neat small saw!

if you buy one, take one with electrical or pneumatic drive! with hydraulic or manual drive it's hard to adjust the wire pre-tension during cutting, especially when cutting difficult pieces or material!

the combined wallsaw/wiresaws are pieces of junk, take a real wire saw for professional use!

keep it safe dude! and never under estimate the wire! the wire goes like a bullet trough your head...