Like everything else on this planet, it's relative. First of all, it depends on how long the deposition is - they generally charge by the page. If you are in NYC, costs range from ~$4 to $8/page, depending on how quickly you want the transcript. Upstate, it's a little cheaper, usually ~$2.50-$5/page. Then there are appearance fees, set up fees, shipping/handling charges, and any other extras you might want (miniscripts, word indexes, interpreter, etc).
Generally, for a 2-hour deposition in NYC, it would run you in the $1000 - $1200 range.