I have a request for you lot please

My photo guru is off travelling in the non-touristy parts of Cambodia and has decided that if the X10 image quality is good enough for me, then it will be plenty good enough for her too.
She is planning to carry the X10 around her neck for opportunistic shots and for use in places where using a 5DII might be indiscreet.
Please can you recommend a book on how to get the best from the X10.
She's an experienced photographer in her 70's and normally uses a 5DII to shoot people pictures, somewhere in the grey area between street photography and portraiture.
All opinions welcomed - thanks!