You should have one with your sound card/onboard audio drivers but some programs like Foobar have one built in that is good. If you're asking about presets, the "best EQ" is going to vary and unless someone has identical equipment (and ears) it's not going to do a whole lot for you.
Was thinking more a physical equalizer. Something that physically gives me control over lows/mids/highs.
Yeah I like the idea of having the dials at my finger tips. Not sure it's something I'd get right away but if it looked right to me I think it would be nice to have. Would be happy with something fairly simple. Low/mid/high would work.