I want to start building these boats and I need suggestions on a beginners build. Initially I want something to use as a tow/rescue boat for my RC race boats when they flip over so I thought a tug might be really cool. I ultimately want to be doing scratch build boats where I make each individual plank like my grandfather did but maybe a kit is my best first boat bet? What recommendations do you have?

Thanks,
Aaron

OH and I am already starting a Tugster build from Zipkits but I am not considering that my first build. My first real build will be something much more scale in appearance and more difficult to build.

My first question would be how big do you want to go? Dumas has some decent scale boats that might work for you. A couple examples would be:
1) Dauntless Dumas Products Estore
2) USS Whitehall Dumas Products Estore
3) City of Buffalo Dumas Products Estore
4) Mt Washington Dumas Products Estore
5) If you want a tug, this should get you to several - Dumas Products Estore

For a rescue boat, a Springer is a good option. Mostly simple flat panels, very basic drive. The flat front makes it a good pusher, for rescues further out it can tow a line to snag the victim.
When you want to "go complicated", the world is full of plank on frame kits and there are plenty of sources of ship plans. Some for models, some actual ships. A lot depends on what type of ship/boat you want.