I'm a young'un, but I have been bowling leg-spin for as long as I can remember.
I have quite a few deliveries. Stock Leg break, Bouncier but less turn leggie, big leggie, off-break, top spinning leggie, top spinning offie (terrible delivery). I would love to know how to bowl a googly though!
Most are just variations of the stock leg-break, but they get quite a few batsmen in trouble. I love bowling to adults, but not to juniors- Juniors try to smack it all the time, whereas adults are conservative and more likely to get out.
Saying that, I managed 5-12 for school by dropping the same legbreak on middle stump. All were chipped to silly mid off, which shows that if you get it in the right place, rich dividends will hopefully occur!
Try The Art of Wrist Spin Bowling, by Peter Philpott and The Art and Science of Cricket, byt Bob Woolmer. Both are superb books and are very helpfull!