good and cheap, i would look at the p5b-e, if you value something like intel matrix raid. $150ish.
if you don't care for that, then the gigabyte s3 would be nice. you could even overclock quite a bit with it. its about $90.
if you really want cheap, and are positive you won't be ocing (or won't want to somewhere down the line) then the asrock dual-vsta. it will run the e6400 no probs at stock speeds, and only costs about $50.
may i ask why you won't be ocing at all? really, with the s3, an oc to 3ghz would be so simple, and would probably do it on stock vcore/cooling.