With Princess land tours are there any amenities, such as meals, included at the lodges and on the train or is it just transportation and lodging
You have to read each itinerary. At the end of the description of each day's activities, there's a code for included meals -- "[B,D]" if breakfast and dinner are included or "[L]" if only lunch is included or whatever.
I think that all of the cruise lines' land tour packages are rather expensive for what you get. You probably would do better to arrange a transfer to or from Anchorage International Airport through your cruise line, reserve a rental car there, and reserve hotel rooms in advance for the land portion of your trip. Alaska's main roads are generally in excellent condition, so driving during the daytime is no problem at all.
Meals are not included, unless specifically mentioned. Budget 50% more than you would at home.
Most important in any cruisetour selection, is to know what you are purchasing, most do not. A significant concern should be Denali park, NEVER choose an itinerary with the Natural History tour, a complete waste, missing out on a big portion of the park, don't expect much, if any wildlfe. Only goes the public road distance to mile 16. At the least you need the Tundra Wilderness tour, which goes to mile 53. Farther equals wildlife and scenery. Factor in all the transit times. They are significant. and a tour that looks good on paper, especially the shorter ones, may have all your time in transit.