If you're into mentalism, "M.I.N.D." is a great book to work with. It is a collection of Lee Earle's writings, along with a bonus CD that has a lot of nice extras on it. Lee does a nice job here of presenting a lot of different effects, and also of explaining the motivation behind them and updating some of his earlier stuff with a sentence or two of new handlings or thoughts.
Unfortunately, if you're not using a special clipboard prop Lee describes, the first section of the book might not mean a lot to you. It can be adapted to other types of readers that use carbon paper or the like, but the beginning of the book is geared that direction. Stick with it though, as there are a lot of great effects still to come in those pages.
Lee goes into detail about his billet work, and he makes an excellent case for its importance in mental magic. One effect he uses involving his photographs and different ladies from the audience leaving a kiss on them as he figures out who is who is particularly nice. The method isn't brand new, but his handling is great and I can honestly say I probably would never have caught it (he includes a couple of the photos in the text so you can see how it's done). His reasoning behind choosing this method rather than gathering items from the audience is especially sound in today's litigious society.
Earle's earlier work is actually some of his most versatile for the average performer. There are several headline prediction variations, and they each have a strength and weakness. I think this allows the individual performer to figure out what's best for him. Earle also includes everything you'll need to print out for some great performances involving fake stock certificates, headline predictions matching a seemingly innocent photograph, and handwriting samples.
The price is a little steep, but for the vast range of material it's a good investment, even for the beginning mentalist.