I wish I could give you a definitive answer, I haven't toyed with lionel since I was a kid... some 38 years ago. A clue might be printed on the transformer, but that will be a ball park estimate. The trains may be older or newer. My advice is to start looking at listings on ebay and see if you can find matches to them. I will venture a guess and say you found a bit of $$ in that barn find!! Not millions, but certainly in the hundreds for the lot.. It all depends on when it was made and how many are left.. Good luck in your search!!
Thanks! it works it came with 2 train stations, 2 generators a log cabin lionel set, with all horses and cows, all tracks, rail road crossing . I couldnt find no set like this on ebay or anywhere else.