I have an atttached 1000sqft garage with in floor heat, I tend to have build of moisture on my windows in winter from the evaporation of water off our vehicles. Our local building code does not require a powered ventalation system. I would like to install some type powered venting sysem but I don't what size and kind to install

This is a heated garage and you want to vent to the outside? How about a dehumidifier?

a small HRV would do the trick if the garage is heated. I think panasonic makes a little unit that would be pretty ideal for a big garage like this.

Our garage isn't heated but stays above freezing so we have the same issue. What I did was simply add plastic to the windows. I think the ones that are in there are really cheap with no "R" value to speak of, so they get condensation on them really easy. I wish I had put "real" windows in with storms, and then it wouldn't be an issue.

Other than that I would go with a small HRV to dry it out. Ours is only a problem when the cars come in covered in snow.

if you're not heating it, no need for an HRV. just a small fan would do.