Do IC's in DIP sockets require an extraction tool?

Yes, you can use an extraction tool for removing ICs from DIP sockets (you can get them for PLCCs too) but something like a screwdriver wiggled underneath gently at both ends works fine.

The main thing to avoid is lifting one end up too high and bending the pins, so you lift one side a mm or two, do the same with the other, etc until both ends are raised flat and the chip can be lifted easily from the socket.

If there is adequate clearance, a typical screwdriver will work very nicely for removing DIPs from sockets. Insert the blade between the socket and the chip (not under the socket!), then twist gently in alternate directions to raise the two sides of the chip. Apply gentle pressure on the side of the chip opposite the side being raised, near the corner where the screwdriver is being used, to ensure that both ends of the chip rise by about the same amount.

One "tool" that's even better than a screwdriver, though I'm not sure where you can find one, is the L-shaped metal piece from an old-style PC case which screwed in to cover up the holes where I/O cards go. Not sure how best to describe it. Old-style PC cases are a bit hard to find these days, though.

BTW, I've yet to find a chip extractor tool that worked better on DIPs than the above-mentioned PC case piece.

Wiha has small screwdriver-sized crowbars for extracting DIL-ICs. With these you can push up the far end of the IC from below, even if you can only get at it from one side.