I recently purchased Claude Gordens 'a systematic approach to daily practice' from musicroom.com and to get free postage i needed £2.50 more (as we all like free postage!) anyway my eye was caught by a book called 'Embouchure builder for trumpet' by Lowell Little, i thought i'd never use this book as i would be to basic, i was proved wrong! what a fantastic little book! I personally reckon every type of player could benefit from it! and all for £5.50!! the exercises are fairly basic to begin with and get harder towards the end (presumably as the embouchure becomes stronger!) i'd seriously recommend checking the book out!