Here is a link to the windmax 1kw unit currently offered:http://www.greenpower4less.com/windmax_004.htm
With grid tie there are two options:
1) Hire a licensed professional to design and complete the installation to comply with local and national safety standards and codes.
2) Buy a "Grey Market" device that is likely NOT going to comply with electrical codes and significantly increase the chances of reducing your edifice to a smoldering pile of ashes.
This is an example of the "Grey Market" devices:http://cgi.ebay.com/1200W-GRID-TIE-INVE ... 2309d028ea
Please Note: I have not seen a serious review of any of the devices of this type; they are almost certainly in violation of numerous electrical codes, and, in my opinion, are not likely based on sound design principals. Devices of this type will NOT run any standard, modern electric meter "backwards", and are quite likely to generate a great deal of "noise" that may or may not disrupt or damage devices in your home. I say these things despite the sellers assertions to the contrary, and I could be wrong, but in my experience, "If it quacks like a duck, walks like a duck and flies like a duck, likely it is a duck."