Anyone have advice on nicest inexpensive hotel near Seatac airport?
By "around the lakes" James means Angle Lake and Bow Lake. Not that the lakes themselves are an attraction (especially not Bow Lake), but that is the are where the acceptable hotels are. I agree with him that heading a bit out of the area, especially north (unless you're going All the Way north to Seattle), is probably not what you're looking for.
When you arrive at Seatac, you will need to call your hotel for a shuttle. Unlike some US airports, Seatac doesn't have the always-circulating shuttle vans. I waited for an hour before I realized I had to call my hotel for a ride. I found a board with hotel phone numbers and a phone nearby.
We usually stay at the "Sleep Inn" the night before an early flight. It's not expensive (or fancy), but it's quiet and clean and they serve a good breakfast buffet. Shuttle to airport begins at 4 am. Sleep Inn is rated #1 of Seatac hotels on TripAdvisor.