Re: Lake Of The Woods - Rainey Lake
For Rainy, you could probably leave it at the Voyaguer's National Park (VNP) Ramp or use Sportsman's or Rainy Lake Marine. Both of the latter charge for launching and parking, if I remember right.
Or if you are staying at a lodge or motel, you should be able to leave it there.
Also, you might want to travel to Kabatogama, about 25 miles south of International Falls. Great ramp at the Kab Visitor Center for VNP. There is also a state run campground that has a boat ramp right there (Woodenfrog). The campground has water, bathrooms and possibly electric. Camping in VNP requires a camping permit, which has been free and available at park visitor centers.
I would suggest having lunch or dinner at Kettle Falls Hotel, which can be reached from any ramp on Rainy or Kab. The trip from Kab is easier and shorter. Just make sure you pick up a chart for the lake(s) you will be on. These lakes have lots of reefs and rocks. Also, you will be traveling on the international border, so if you have a passport card, you want to bring it. You are not able to land in Canada without checking into Canadian customs and with US Customs when you get back.
Fishing licenses are required on all lakes, Minnesota on the US side (and required in the park) and an Ontario license if you cross over. Make sure you have GPS to stay on the US side if you don't have an Ontario license. The Ontario Ministry of Natural Resources frowns on those who cross over "in error".
If you are interested, I can also give you a few points of interest here. Also check out the VNP web site for more information.
As for Lake of the Woods, sorry I cannot help you there.