This post, ironically, isn't as super as the other ones, but that's ok. Sometimes it takes a while - even for a popular show - for an adaptation to trickle into continuity. At any rate, Smallville is already on its way to becoming one of the all-time high sources of canon immigration.
Lionel Luthor first appeared in the Smallville pilot (2001). He first appeared in comics in Countdown #34 (September 2007), but was first mentioned prior to that in Teen Titans #26 (September 2005), as Lex was going to name Superboy "Lionel" after his father.
Chloe Sullivan first appeared in the Smallville pilot (Fall 2001) as one of Clark's friends and the editor of the Smallville Torch. She made her first official appearance in DC Comics in the Jimmy Olsen back-up feature of Action Comics #893 (November 2010). The comics character combines Chloe's journalistic background of the early Smallville seasons with her relationship with Jimmy Olsen of the later seasons. Chloe - or rather, her name - made two earlier cameo appearances in Superman: Secret Origin. In Secret Origin #1 (November 2009), her name appears on a cast, and in Secret Origin #4 (March 2010), Lois has a Post-It reminding her to call Chloe.
Left: Green Arrow since the 70s
Middle: Green Arrow on Smallville
Right: Green Arrow beginning September 2011
In Superman/Batman #44 (February 2008), Superman mentions that Kryptonite can give powers to humans and turns them into a twisted version of themselves. This is a reference to Smallville (2001) - specifically, the plot device that gave him villains to fight every week for the first couple of seasons.
Granville first appeared in Smallville as a neighboring city of Smallville. It appeared in a similar capacity in Superman/Batman #13 (October 2004).
Black Kryptonite first appeared in the fourth season premiere of Smallville (2004). It appeared in a similar capacity in Supergirl #2 (September 2005).