There are a few different reservoirs available for nice walleyes but from what I understand, most of the panhandle is going through a severe drought with many reservoirs suffering severe drawdown. My recommendation for walleyes would be Merrit Reservoir south of Valentine. A lot of nice fish in there, plenty of trophies. You are in a win win situation there. If the walleyes aren't biting, there are some refuge lakes where you can score some nice pike and outsize panfish. An internet search on a search engine such as Yahoo or Google for Merrit Reservoir should bring you up plenty of results for lodging etc and a quick search of the Nebraska Game and Parks will help you find out the necessary info on out of state fishing licenses as well as purchase prices.