The Lonely Planet guide is often way out of date, so be careful if you use this as a reference, even the most updated version.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 :-)

The places to stay in Nepal are varied in many ways! Google accommodation Nepal for yourself! However, HwH founder Kira Kay, makes the following personal comments:

Kathmandu Hotel recommendations:
For those who prefer a quiet, peaceful location adjacent a monastery I suggest here three options:
http://www.shechenguesthouse.com.np/
http://www.benchen.org/monastery-nepal/benchen-vihar.html
http://www.sakyatharig.org.np/guest-house/index.html

For those of you who prefer some luxury, but wish to be connected to the Nepal culture, this hotel is a living architectural & cultural Heritage site:
http://dwarikas.com/

For those of you who might like something in-between (where I stay when in Kathmandu): http://www.hotelvajra.com/

Aside from that there are many options for accommodation in Kathmandu to meet a wide range of budgets and taste. Plus there are various apartments for rent to foreigners at various levels if wish to be more independent. I would suggest simply land for the first few days and get a feeling first as there is so much that may unfold.

Tips: Some of these hotels offer a complementary pick-up service from the airport, I would suggest that you book to ask for this option as it can make your entry to Nepal more relaxed. If you choose a hotel that has no airport pick-up, then I would recommend you organize a ‘pre-paid’ taxi at the exit of the airport, otherwise as you enter into the airport car park to find your own taxi it can be overwhelming!

Additional tip – please check your accommodation on arrival for cracks, if the building room has significant cracks please choose another location, many buildings have been structurally weakened in the recent earthquakes and the often time the owners do not fully realise this fact.