how can i keep live plants in gravel without using too much gravel...?

I just don't use gravel. I don't like gravel because I'm slightly paranoid and always scared that my goldies are going to choke on it. What you can do is aget a little terra cotta pot, or a glass votive candle holder and put the plant inside of it. Then you can fill it upp with gravel, river rocks, pebbles, marbles, whatever you like! They actually look pretty cute in the terra cotta plants. It makes your aquarium look like a little underwater garden! I know that myself and a lot of other people do this. I just got my first live plants yesterday and did this and I think it look pretty darn cute!
You could also always try attaching them to a suction cup and putting the suction cup on the bottom on the tank.
Anyway, that may or not be what you wanted. Oh, well.

I have a bare bottom set up. The way I keep plants is to get small pots, fill them up with gravel and plant my plants there. This way, the gravel don't have to scatter all over the tank

You could get some plant substrate, like flourite, it is smaller than gravel, and then put some river rocks on top of it. This way the plants have a good substrate for rooting, and you don't have to worry as much about the goldfish rooting around and swallowing gravel (since the river rocks will cover most of it). This is what I plan on doing in my tank...though I'm going to put a small layer of regular gravel on top of the substrate, and then the river rocks, just for looks, and also cause I heard the substrate can sometimes make the water cloudy.

I did a tip of the month on this subject

where's it devs???

Here ya go!...
Tip of the month on plants

Thanks Andrea....I meant to go edit,and add that in my post,and forgot!!!

Also very interested in starting with some live plants some time soon and couldnt get the link to work, but I think this one will:

linkage to Devs' tip!

*goes off to read that one too*

I had flourite in my tanks, and it only clouds the water initially when you first put it in, or if you're digging around in it planting, etc. A small micron filter pad will clear up the water pretty quickly. Another benefit of planting in pots is that you can use a high quality expensive substrate because you won't need as much as you would if you were covering the whole tank.