Skinny,
The free ramp is on Black Creek North of Port Dover. It is on Concession 2 just east of the Cockshutt road under the bridge that crosses the creek. I have attached a map link with a flag marker on it but the marker is just a little further east than the ramp. I haven't been there for a couple of years but as I recall, it is really only good for smaller boats and it's a LONG ride to the lake...
http://maps.google.ca/maps?f=q&source=s_q&hl=en&geocode=&q=concession+2+woodhouse+road+port+dover&aq=&sll=42.798046,-80.19011&sspn=0.012879,0.0421&gl=ca&ie=UTF8&hq=&hnear=Concession+2+Woodhouse+Rd,+Norfolk,+Haldimand-Norfolk+Regional+Municipality,+Ontario&ll=42.800565,-80.192299&spn=0.025757,0.0842&z=14