my two favorites?
the already mentioned Sensational Knitted socks
why? lots of variety. (of stitch patterns)
each sock has directions for 4 DPN's, 5 DPN's and 2 circs' (2 circ and ML directions are virtualy identical)
What i don't like? Occationally unclear directions (she explains philosophy of socks in early pages.. if you don't read an just jump in and make socks, some directions are hard to understand.
Second: Knitting Vintage Socks.
Why? lots of variety. opening chapter explains different types of heels, and give generic directions for 4 styles of Heels, and 6 styles of toes..
what i don't like: again--be sure and read opening chapter..
titles of socks remain unchanged (so its still "French Childs sock" but the pattern has been updated and its now an adult size sock!
there are other good sock books, but these two aren't good.. they are great.