i have a problem where i cant play my own stuff good because my hand gives out before the song is finished. i play fast metal/thrash so do you guys have any endurance exercises you can suggest?? its my biggest problem right now other than not having a drummer
^ stop playing all tensed up. i used to have the same problem until i realized i was exerting WAY too much effort to play as fast as i do. you should re-evaluate how you play as i would bet the big $$$ that you have a death grip on your pick and probably have really tense hand/wrist muscles when you play.
a. practicing every day, it wont do you any good if you practice every other day, you wont be able to build on the previous days work

b. start pushing your limits with tremming and whatnot

c. make sure your relaxed

and the most important thing to build stamina:

d. practice whatever it is around 3/4 the actual speed for a LONG amount of time, just sit there and loop the thing over and over and just keep playin it til you get tired, it allows you to a. play it faster next time and b. have the stamina to do it faster for longer
Quote by beadhangingOne
There is no music but metal and muhammad is its prophet.
Which hand is getting tired? If it's your picking hand, do a lot of tremolo and stuff like that. If it's your fretting hand, do tons of legato and bends.

e  |---------------4h5h7p5p4h5h7p5p4---------------|
B  |-4h6h7p6p4h6h7-------------------7p6p4h6h7p6p4-|

Just play the exercise above for as long as you can on a clean channel. If you can do it for more than 3 minutes straight, it's not your stamina that's holding you back. Make sure the notes ring out clearly.