I'm writing one, but concerned it's not long enough! I think it will be aimed at kids about 12 years old. Does it matter if it's short, will anyone publish it? I think it will be about 30,000 words. Any info or links appreciated. Would-be writer!
Good luck, firstly; 30,000 words would be a superb achievement.
Many novels would be 60,000 words plus.
Childrens books, which are difficult to write, can sometimes be much much shorter. Have you looked at Writers and Artists Yearbook 2007 in library? The names of agents and their office contacts are there.
There are also specialist magazines in Easons which give such guidelines from time to time.
Depending on the sub-genre and intended reader age, most young people's novels come in at between 30-45k. Some established writers seem to get away with a lot more than that - JKR is one who comes to mind.
30k sounds about right, but do remember that you'll probably be editing a fair amount of that. However better too short than too long.
The average number of words per page in a black and white book is 300 words. 30.000 would make it say, 100 pages the least perhaps? For a children's book, that is actually a lot already! Good luck!