I used to go through the same agonies until someone got me the Bible for a gift - I suppose it makes sense they won't give all away free when you can pay money to buy the book itself.
Yes, Chambers 11th is a good buy but maybe you should wait as they are about to issue a 12th edition. Compilers mostly use Chambers. It's the compiler here - very grateful when one of you asks a question as I live overseas and the on-line FG never tells me which crossword they have used this week. One kind solver often lets me know but this site is a real asset!