I wouldrecommend you to hang out in forums related to weight loss and find out what is the hottest trend among this crowd. Nowadays, low carb diets are hotter than low calorie ones. You might want to createyour ebook around low carbs instead ;) (just a thought).
Or you can just convince your customers of why a low calorie diet would be better than a low carb diet...
Anyway, here are some tips I cangive you related to the development of your ebook and marketing strategy to kick-start your project.
1- Get your recipe book and sales page done before you do anything. Create a great qualityebook, dont sell crap. This crowd is highly sensitive and will not hesitate to ask for a refund if your product is crap. If you can't make a great sales page (that actually sells!), get some procopywriter and graphic designer to do it for you.
2- Get together a *good quality* report of 15-25 pages long and create a squeeze page offering the report for free in exchange of email addresses (aka listbuilding). The report *must* be of good quality! First impressions count in this business. And since your free report will be that first impression, you need to create quality. This will bring awesomeresults in the long run (hint: when you launch your ebook)
3- Before you start driving traffic to your squeeze page, have at least 20-25 pre-written follow-up messages with good informationrelated to weight loss. And since you are going to sell a low-calorie recipes ebook, I would recommend you to have messages about how a low-calorie diet helps burn fat and lose weight fast.
4- Now, it'stime to promote your squeeze page. Do some keyword research, forum marketing (no spamming), get articles done targeting the keywords you found useful during kw research, get some videos done with...