I feel your pain -- I did it in 2007.  My advice would be to borrow or purchase a comprehensive book with sample tests and photos (or, CD with photos).  There are a few out there on the market; some wirtten by Lactnetters!  Take one test without any prep -- see which sections you did poorly on, and concentrate on those areas for study.  Then, take the test again after you've done some prep. 
 
Be prepared to feel nervous, stupid and ill-prepared at various stages of the game, even if you've been a practicing IBCLC for many years.  I don't think any of us can escape those feelings!  I know I didn't.
 
Just to make you all jealous:  Kay Hoover lives in my part of the world, and for several years running she has done exam-prep presentations at our local ILCA affiliate meetings where she shows ALL her slides.  She has well over 200 -- probably more.  We sit around and look at weird breasts and odd nipples and something-wrong babies and whacky tongues and rainbow-hued milk and talk everything to exhaustion.  
Liz Brooks, JD, IBCLCWyndmoor, PA, USA
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