There are lots of great online game stores you can get these from. These are the kinds of games that people who play boardgames as a hobby (rather than an occasional family thing) play. No more roll-dice-move-pawn, these have some thinking involved. (Some more than others!)

If you're interested in trying something new - I would suggest starting with either Carcassonne or Ticket To Ride. Both of those are very easy to learn, quick to play (under an hour) and a whole lot of fun. Try one - I'm very sure you'll be glad you did!

Some stores that carry this kind of stuff are:
www.fairplaygames.com
www.bouldergames.com
www.funagain.com