You can tone the muscles underneath, but unless you're doing cardio/burning fat then all those muscles will be kept hidden. (For me, I'm pretty sure I've got a six-pack going on somewhere down there ... but I've still got a lot of stomach fat to work off before it'll show lol) As myfish said, you've got to do both. Try Jillian Michaels' DVDs... she likes to combine strength training with cardio for the "ultimate workout". And tried and true... it WORKS. Trust me!!!
But also, don't be discouraged by the scale. If you're losing inches it means you're looking better, regardless of what you actually weigh. And for me, that's what counts. I've seen 210 lb female basketball players who are nothing but muscle. They're in shape and they look great...despite the scale.