When we started talking about our California National Park road trip and our Grand Circle road trip (UT, CO and AZ), I turned to two web pages and apps I use a lot for travel planning. One is Roadtrippers. I love their site and app. The website can be a little buggy with older browsers and computers, but it has helped me map out a few trips now. We used the app in Florida to get from Central Florida to Saint Augustine and back without a hitch. You can view where you are driving on the app and see restaurants and interesting sites nearby that you may want to stop at. It also shows hotels and gas stations if you want. I find the estimated times that it will take you to get to the next stop pretty long, but you can get a rough idea by the distance. If you are looking for ideas, there are also fun stories and trip suggestions on their website and Facebook page.
My favorite trip planning tool (other than TripAdvisor and guide books) is TripIt. I can make an itinerary and plan out our whole trip. TripIt lets you forward air, hotel, cruise, Open Table, and car rental confirmations to them by email and they automatically load them into your trip itinerary. I have 4 trips on there right now and 90% of the time it knows what itinerary to send the confirmation to. When it is not sure, it keeps them in a file for you to load. It shows you weather and maps for your locations. You can plan your trip on your home computer and all of your info will be there in the app. You can also link it to your cell phone calendar. I love having all of my confirmation numbers and times in one place. Best of all they are both free!