The key to covering up a pond liner is to ensure the edges of the pond have a shallow slope so the pebbles/gravel you cover the liner with don't slip down into the pond.

Here's a sketch of what I mean

http://www.flickr.com/photos/31559373@N00/4122848230/

You might find my blog on my own pond has some useful information in it( my blog on GOY)

http://www.growsonyou.com/anchorman/blog/11683-replacing-a-pond-liner-and-creating-a-new-pond

Here's a link showing a few ponds I've designed/built which might give you some ideas.

http://www.flickr.com/photos/31559373@N00/tags/pond/

you should find the liner becomes almost invisible as the plants grow. I cant see how you would hold the stones in place any way. what size are you hoping to make it? the bigger you can the better as you'll only want to make it bigger next year. :o)

see my sketch above

thanks for the advice and links all most helpfull

have you seen that pebbledashed butyl excuse my spelling . thats very good and in different widths . theers also a new sylicone that drys underwater and doesnt kill your fish now . i built my mums rill in her pond using it . its realy effesctive .