Well as you all pointed out there is not a Lionel Guide book covering later than 1995.
So I have found a source of information on Lionel trains latter than that - Lionel Train catalogs. One can get them from your local train dealer. I pick up some at train shows, often a year or two older, left by dealers or by others who no longer need them.
I have Lionel year 2000, 2003, 2005, 2007 ,2013 and some 2016. Some later years are smaller and specialize at Ready to Run or Christmas, etc. Also have a couple K-line and MTH and American Flyer. These all have better pictures than the guides and similar descriptions and even the list prices.
It is not necessary to have every year, just every few years to keep current.
Best of all these are FREE.