I need a recommendation!

Firstly, I want to bue an e-dictionary for advanced level, but I dont know whick to choose. I dot know if the CDROM goes along with Oxford or Cambridge dic has the same amount of words as the book itself? I have Oxford Learner's Dic, and the CD Genie goes with it is awful. So I want to have an advnaced e-dic on my PC. Could you please recommend one?
Secondly, I'd like to buy an advanced grammar book, as detailed and deep as possible, to develope academic writing skill and grammar. Which book is the best choice among many of those in bookstores? I really need it.
Please help me, thanks in advance.