I picked up an older oak desk today, very typical style I've seen many times before but finally got one of my own. It's worn, and so I'm planning to refinish it, but I'm not sure what to do about the top. Heck, I don't even know what the top is made out of. Anybody have any ideas, and what the best way to go about refinishing it would be?

Here are a couple pictures, first of the desk as a whole, then a closer shot of the top, including some of the worst damage on it so you can get an idea of what I'm up against. It sure doesn't look like any kind of wood insert to me.

{{!gwi}}
{{!gwi}}

There is also some damage to a couple pieces that I'm going to repair, in fact a couple small trim pieces I expect to replace outright -- any trick to finding the best matching oak?