I can't find any. What I've found are all outdated craps, including the ones on youtube and most of google's search results are useless too. I've just came to start modding from writing Bukkit plugins, and some start would be really useful.

Whenever you're doing something where there is something similar in vanilla Minecraft, you don't need a tutorial. Just look at the source for that similar thing. There are lots of GUI classes with buttons, and a couple with text fields (if you mean input field). So just look at those and copy what you need for your version.

 

That's how the people who write tutorials figure it out, so you might as well do the same.