Often, I hear a song that I would like to learn to play, but I can't find good tablature on the Internet. How do I write up my own tab quickly, so I can use it for reference in the future?
If you don't already know how to play the song, you will have to go through the process of learning by ear. If you can, try searching for the chords of a song; there are usually more chord charts for songs than there are tabs. Knowing the chords will give you a basic idea of where to start.
When it comes to picking out riffs and lines by ear, try starting to pick out distinct notes, and hearing how they change, either moving up or down in pitch. Some people are better at hearing how much pitch change there is than others, and will therefore be able to get the riffs and solos down quicker. If you are really stuck, just try playing random notes up and down the neck until you get the right one, and try and go from there.
There are other things you can try to help you learn the song without the help of tabs. The first is watching live footage of the song, and particularly the shots of the guitarist. Seeing their hand positions on the fretboard and where they are on the neck may help you with knowing what frets they are playing. The other is slowing down the song with such software such as audacity (free on all major platforms), which makes it easier to learn faster riffs and solos by ear.
Once you know how to play it, you have to tab it out. You want a simple text editor for this, such as 'Wordpad' on Windows or 'TextEdit' on the Mac. As a side note, I would recommend the font 'Courier New' for writing tabs, as each character has the same length, so numbers, letters and dashes line up perfectly on your tab stave.
Start off with your empty tab stave, like this:
E|---------------- B|---------------- G|---------------- D|---------------- A|---------------- E|----------------
where every '-' is a beat, or half beat, or quarter beat, depending on how many notes are played per beat (for example, it will be more during a fast solo). You then have to write out the fret number on the corresponding string for each note played.
Remember to include standard tab notation, such as 'b' for bend, 'r' for release, 's' for slide, 'h' for hammer on, and 'p' for pull off.
Once you are done, play your tab, to make sure timing seems right, and that you have the right fret numbers.
Another important thing to do if you are using it for future reference is to label each different section as the part of the song it is from, so you do not get lost in your own tab!
Hope this helps :)
If you're going to want to transcribe music to paper I'd really recommend taking an ear-training course, along with an intro to music theory course. Usually they go hand-in-hand, or are co-requisites.
You'll learn how to listen to music and pick out voicings, and then also learn how chords are built, how keys are defined using sharps and flats, all which will help you make good choices for naming the chords.
Music instruments have lots of "enharmonic" tones, which means the note sounds the same but is named differently because of the key its in.
I would also recommend some tab tools to make formatting the tab easier.
All three of these programs will give you a good interface for creating tabs and a quality output at the end - in either text or PDF, and sometimes other formats.
But most importantly, all of them will play back the tab for you, so that you can verify that the tab you've entered matches the song you are tabbing.
I have and love Guitar Pro, but any of these would be beneficial to you.