Though I do not like the direction this person who made the thread is taking when speaking of why people wish to believe in something more since, even though the majority of things shown on that television series has been debunked, it is just not true and most are only searching for the truth, but
here is a link to a somewhat interesting thead that may get you started on finding information proving or disproving it. Also, a lot of the "experts" on the show are a bit sketchy.
I'm sure you will notice that it talks more of the series before Ancient Aliens, which was Ancient Astronauts, but it was a knock off -sorta- or maybe more an extension. I'm not really sure where they were going with it, but to me it seemed like the same basic thing.
Personally, I believe that somethings described to be debunked were not debunked since I have stumbled onto a few things that prove otherwise. I do believe in other worldly beings, whether they were here first, remain here, or visited us and left. The Ancient Aliens and Ancient Astronauts bring up some interest points but many things talked about as proof or near proof were exaggerated.
Of course it is your choice to believe what you will and so if you did like the series, you may want to read one of the main "expert's" books which is titled "Chariots of the Gods". It's not a bad read, but it too sounds exaggerated and leading into fictional. What (proof/information) we have now some say we do not have at all, and what we do not have some say we do, so it's a bit of a ******** (not militia-termed kind) in my opinion. =P