Are there "blind spots" in the fossil record, i.e. kinds of environments from which no fossils have been preserved?

There are certainly environments where the liklihood for fossilization is extremely low - Basically anywhere that is eroding rather than depositing.  You would be unlikely to get fossilization at the top of a mountain for instance (because the top is always weathering away).

However, the animals that die in such places will likely have their remains end up in the same place as the eroded sediment.  So a goat that dies on a mountain, for instance, would likely get washed down the side of that mountain and end up in a river channel further down where sediment is being deposited.