There are a lot of sites that are set up to share malware.
Oh wait - for testing purposes.
Leave a VM connected to the Internet with no a/v on it for awhile and you can probably get a good sample of what is currently in the wild. I remember years ago, I had just finished connecting my Dad's PC through a 14.4 modem, and within minutes Zonealarm had already reported numerous blocks. That was like 25 years ago and I don't think the environment is any nicer these days.