If you are needing chains, you can often find them for a good price at auctions. I have several in different length and strengths, probably didn't spend over $10 on any of 'em.
As previously stated, the 14' log chain and a 8' or so version of the same are what I use the most. I hardly ever use the really heavy ones, or the really long ones. For a long pull such as guiding the fall of a tree that needs to come down, I usually use a cable and snatch block.