If you don't mind paying for water, most RV parks will let you fill for $5-$10 (ask to use their potable fill and dump). Also add the Watermill Express stations to your list, again paid, and if set on free, check gas stations and truck stops, etc. We usually don't mind paying that ~$10 for a week of water, especially considering the costs if we were paying for accommodations.
rvdumpsites.net and campendium.com usually have comments on facilities - including whether or not they have potable water.
We use large bladders to get water in bulk in addition to collapsible 5 gallon jugs, so that when we do pay for water at a RV park, for instance, we get enough to last us a while.
