You can get amber with bugs in it on ebay and other sites - just be careful where you buy from. Some of it is copal, which is resin that hasn't completely hardened into amber, and while it can have real bugs in it, they are are younger, modern species. IIRC a lot of it comes from the Dominican. Baltic amber from Poland and the Ukraine etc is the real deal.
Then you have the jackasses in China making fake amber - plastic. Some of it is super obvious, a perfectly centered scorpion, or a coiled snake or lizard. (For awhile I spent time reporting the frauds, but they just came back under new names. If it actually comes from China, run away!)