Book on understanding varieties of hops and yeasts?

I've been doing a lot of reading about brewing since I'm new and a lot of books touch on the subject of yeast strains and hop but don't go into depth on things like flavor and varieties. Are there any books you would recommend that focus solely on yeast and hop varieties and talk about their characteristics? Or, is it more of a, "try it yourself and come to your own conclusion" kind of thing?

Solely wondering as I start my own recipes, what varieties of yeast and hops I'd like to experiment with based on their characteristics.

I do not know of a specific book but I do now that Wyeast has "profiles" list on their web site for yeasts. As for hops I know there are/was people working on a profile guide here on HBT but I have no idea what became of that...also I am pretty sure that http://farmhousebrewingsupply.com/Scripts/default.asp has the profile listed with the hops. click on the hops on the left, then pellet then mouse over more info...

Jamil Zainasheff and Chris White ( White Labs ) just released a pre-order of their new yeast book. You can preorder a copy signed by both authors at http://www.thebrewingnetwork.com/store/index.php?main_page=product_info&cPath=12&products_id=140&zenid=0888151195c8657859411073a90f3534

Due to arrive in early October.