Hobby Lobby has lots of options in their "outdoor/spring/garden" section--it's seasonal. Of course, you'll want to get something that matches the style of the statue, but I've found several different pillars etc. that work well. I've used a clear trashcan from Bed, Bath, and Beyond for a T-800 statue. There are also different sizes of candle holders that are also clear cubes (Michaels). I used a silver, metal pencil holder from Meijer for my Ultimate Iron Giant, a black candle stand from Hobby Lobby for my Rocker Biker Girl, a black pillar for my Bowen Hellboy from Meijer, and others for PF Ash and other statues.
Basically, get creative. But I think it's very important that the riser compliments the statue itself.