We hired kayaks from 3 locations in Greenland in 2003. We found them all with Google or via the main, and excellent, Greenland Tourist site
http://www.greenland-guide.gl/
1) Narsarsuaq - manic frenchman named Jacky Simoud
http://www.blueice.gl/ Some of the gear was a bit iffy - e.g. mega leaky bulkheads
2) Manitsoq Tourist Office - excellent gear, and excellent service/pre trip briefing from local guide Adem Lybeth.
http://www.greenland-guide.gl/maniitsoq-tourist/kayaking.htm
3) Ilulissat. Tourist Nature run by Italian, Scivoli Silverio.
http://randburg.com/gr/touristn.html
I presume this is for 2006? - transport to, and within, Greenland generally needs to be booked months ahead.