Or you could drive the other way into Michigan and fish the Muskegon or Big Man. There are fish in the Milwaukee, but to me its more of an urban setting instead of wilderness. Not a bad place to start tho.
In fact we are having a spey clave there this May, losts of goodies to play with and you learn a bit about the river to boot.
We can talk more about this off-line, I'll shoot you an e-mail or PM.