I want to self-study Japanese.Where to start?Which books to read?DOUSHIO?

[Red]

Always start with hiragana then go on to katakana and lastly to kanji. (NEVER never use romaji ever, or it'll make it really hard to understand)
I don't know any book but here are some sites for ya

http://www.guidetojapanese.org/learn/
- Has a complete guide (good in my opinion)
http://japanese.about.com/
- Another Japanese course
http://www.memrise.com/home/
- Has many different courses
http://jisho.org/
- To use as Japanese to English
http://www.alc.co.jp/
- To use as English to Japanese
http://addruby.com/
- To add furigana to sites
https://chrome.google.com/webstore/detai...fpcebammhp
- Chrome add that helps you with kanji on sites
http://lang-8.com/
- To share you progress and let native speakers help you!

hope this helps somehow!
がんばって！