Jeff Weaver...oh wait it's buy low not blow. Well in that case I would say Wang of the Yanks althoughhis owner already drafted him on the DL so I doubt you would get him before he comes back.
Carp and Patt are guys with lowered values but I don't think they are "Buys" more like "holds."
CZam was mentioned several times, but how about Dave Bush? He has nice potential but didn't have strong outing recently. I think Aaron Cook is flat out undervalued as a mid-rotation guy or spot starter, no-need to really "buy" him. Despite his 2-0 start, I still think Harang is a buy low because he can anchor your staff and most dont perceive him as a fantasy #1, similar to Lackey in the AL.