Looks like I'm late to the discussion. I like alot of the names already mentioned, but instead of seconding others' suggestions, I'll offer up a few deeper sleepers:'
Hank Blalock, 3B, TEX - The 29 year old remains 3B eligible after playing some 1B in 2008. Blalock followed his 293/358/543 2007 with a similar 287/338/508 line in 2009. But of course these impressive triple slash lines are deflated by the mere 456 ABs in which they occured. Hank battled 4 different minor injuries in 2008, but don't worry about his season opening health status. He emerged fit in September when he batted .414 with 9R, 5HR, and 12RBIs over the last week of the season. So it's the same old fantasy question: 2007 Rich Harden or 2008 Rich Harden? But guessing right only rewards the optimistic.
David Freese, 3B, STL - Receiced from SD in the Edmonds deal, Freese had no trouble skipping from A ball to AAA's Pacific Coast League, hitting 306/361/550 with 26 HRs and 91 RBIs in 464 ABs. Freese is polished and ready both in the field and at the plate, and it looks like he'll get his oppurtunity, while Glaus sits out the first few weeks on the DL.
Brandon Allen, 1B, CWS - Alot of things have to break right for Allen to get significant MLB ABs in 2009, but as Chris Davis showed us, the one thing that can jump start your fantasy lineup is power. Allen has it and plays in an organization and ball park that rewards it. He is not likely to start the year on many rosters, including the CWS, but if age makes further ground on Konerko and/or Thome, keep your ears open for this young Chisock making a debut in August. (LAA's Mark Trumbo fits this discription too)
Fred Lewis, OF, SF - Lewis had something of a breakout in 2008 when he hit 282/351/440 across 468 ABs. Yet his season totals (81R, 9HR, 40 RBI, 21 SB) leave him off cusp of most fantasy sleeper lists. Yet with 100 more ABs, fulfillment of the rumored slide toward the middle of the order, and one more step up in play, I think he is capable of the type of 5 category #s that make guys like Victorino and Hart popular picks.