Big fly fishing question?

Last year my Dad got me a fly fishing outfit, it consisted of a rod, reel and line. I have now purchased a split cane bamboo fly rod, this is my first question, what line should i be using with it? Its a 9ft Martinez and Bird 'Windrush', i have done some practice casting with it and all that happens is, the line, after i try to cast any more that about 20ft with it the line just curls up at the end and falls in a heap, i assume as it was a cheap starter outfit that the line was cheap rubbish, i cant even tell you what brand as it just came on the reel, so what weight and type would you recommend I'm mostly loch (pond) fishing for trout and maybe a small amount of river fishing again for trout so a good quality affordable all round line. The other thing which doesn't help is the fact that the guy in the shop says to just be using some normal fishing line on the end of the fly line (why we go to this shop i don't know) surely that isn't right, what should i have? Both the spit cane rod and the one that came with the outfit are fine and the reel cant have anything to do with the problem, can someone please point me in the right direction?