this is a daydream! everybody would love to have a personal orchestra and make them play whatever craziness in our mind.. would be WOW hehe
but this cant happen (unless you have the money to pay them... and you can try to get people with no lives, so they can do whatever you want 24/7)
anyway the thing you need is a book about orchestration.
There are many libraries where u can borrow one or you can just buy one in a store, i just think that everybody should have one, so that if you need to know what is possible or not on an instrument, if u have not somebody right away to go ask, the book will supply you enough well... unless you need to write something deeply difficult that the book has no answer. but i think if you go to a music school or to a conservatory and you see if you can find some guys that play cello, maybe they can help you out in some way.
