I feel that "know-how" in English is subtly different from "expertise". "Know-how" is often the sum total of little snippets of knowledge that a person hugely experienced in a trade or profession picks up along the way (... it's a lot easier to get at the brake caliper bolt from the top rather than the bottom on a 1958 Triumph, etc.). Rather more "tricks of the trade" than sheer expertise.
Webster (Third New International) has this to say on "know-how", which seems at least partly to back up my feeling:
"... accumulated practical skill or expertness ..."
I sense that the term has become more popular over the past 15 years or so, particularly in the U.S. and is often also used in professional contexts (software engineering, business management), but I still feel that it has a slightly different shade of meaning from "expertise".
Perhaps it's summed up by the fact that I wouldn't necessarily see a statement such as "we have the expertise and know-how to get the job done" as being tautologous, but rather giving two different slants on our abilities.
I'd appreciate anybody else's take on this.