THeres a good lunch not far down river from Grand Coulee at the end of the rocks below the dam I can't remember the name of the little town its in but the water moves fast there at times so becareful but from there head down stream. The alternate is launching above Cheif Joesph dam either at Bridgeport State Park or up pearl hill road both launches are good if you launch there start trolling upriver from there.

Good luck and report how you do.