To practice speed specifically, you could just do (relatively monotonous) 16th note playing along with a metronome. From a strength & conditioning approach, the way to do it would be to start at a tempo which you can play comfortably and evenly for a long time. Then increase the speed in steps until you get to the point where you can't nail it anymore for an extended period of time. Back off the tempo again, and repeat the cycle. Depending on how diligent you are, you may do this several times in one exercise session. However, this will be very boring and has nothing to do with playing music - it's pure exercise (kind of like playing chromatics for the left hand technique).

I think that most people build up speed by playing along to fast songs by their favorite bands. In the beginning, they play it sloppily and a little bit off, but over time they get the hang of it. This probably takes longer than a specific approach as outlined above, but it IS playing music instead of boring repetitious stuff.

A good way to combine speed development with your study of theory is to play pentatonics up and down the neck with 4/3/2 notes per degree. Start in one left hand position, play the scale up and down the strings, then move up to the next position and repeat.

Finger players who need ridiculous speed (like tech death players) usually go with a 3 finger technique, also playing with the ring finger. This takes quite a while to work out in terms of rhythm (playing even notes like 8ths or 16ths with 3 fingers feels weird) and attack (getting 3 fingers to sound the same is harder than 2), but obviously it helps to play faster.

Even more exotic methods are using 4 fingers (including the pinky on the right hand) or using 2 fingers both going up and down (striking the string with the fingernails on the way back. I have not seen anybody do this effectively, but maybe it works for you...

Hope that helps, let me know if I left anything unclear!

Thank you for your very detailed response. I'm used to playing those boring, repetitive exercises. I will definitely begin using your suggestions right away. Thanks again.

Here's a scale exercise that might help. Work through any scale, but play each note as a triplet consisting of the note, the scale tone below it, and the original note. In C Major it would be like this:

C-B-C D-C-D E-D-E F-E-F G-F-G A-G-A B-A-B C-B-C

If you play a scale in one position (on three strings) you'll improve moving between strings.

If you play a scale across two strings you'll improve your technique for sliding between positions.

Thanks for the response. It looks like I'll be quite busy with some very good information.