The Lonely Planet guide is often way out of date, so be careful if you use this as a reference, even the most updated version. The simplest facts can be found here:
http://welcomenepal.com
Some overall basic facts about Nepal can be read:
http://en.wikipedia.org/wiki/Nepal
Current News Sources within Nepal:
http://www.nepalnews.com
http://www.ekantipur.com/en/
http://www.thehimalayantimes.com/
http://nepalitimes.com/
Please note that in general a lot of information about Nepal that was available/published before April 25th 2015 will now be out-dated. Especially with respect to costs – some things may be cheaper but in general there is high inflation added to by the recent events and that will reflect in higher costs.
Some additional travel tips –
Water in Kathmandu is seriously not good! Take care to either use filtered water or purifying water tablets in the water, or boiling the water for 3 minutes. A very good way to have an independent supply of clear drinking water, at the same time protecting the environment, is a reliable water filter, like this one
https://sawyer.com/products/type/water-filtration/
Clothing – It helps to be clothing appropriate to gain the respect of the local people and not offend their views of what is appropriate, especially when we are in village environments. I give you here some guidelines: for women please wear clothing that covers your legs below the knees and ensure tops cover your shoulders and not show too much cleavage. For men please wear long trousers not shorts and wear t-shirt/shirt at all times, going without a shirt is not considered ok.
And for the best pizza ever, find your way to 'Fire&Ice' http://fireandicepizzeria.com/kathmandu.html they are awesome for when you want a break from Dahl Bhat! Oh and the best Dahl Bhat... well that comes from making good Nepali friends and being invited to their home for dinner!
Generally for an awesome - and potentially life changing experience in Nepal - I suggest you ask loads of questions as you travel along and in the old fashioned human way - observe, listen, feel :-)