We can't believe anybody still sells this old camera. You might have to shake the dust off it. We recommend a newer Alpha model like the 850. Here's what we had to say about the Alpha 100 when it was released in June 2006:
The Sony Alpha a100 is the brand's first true SLR, and fair warning to other camera manufacturers that the industry giant is hot on their tails. The Alpha a100 is the culmination of Sony's recent acquisition/merger with Konica Minolta's SLR division. It's not completely wrong to say that the a100 is the spiritual successor of K-M's Maxxum line, and the camera can accept all the same lenses that Minoltas could.