Reddit mentions of Qwik Time QT3 Metronome

If you don't know how to sightread, this is a good time to get good at that. Pack a metronome and a replacement AA battery or two and you're set for 6 months no problem. For books, try:

Jay Weik's Daily Sight-Reading Studies for the Guitarist, Large Print Edition:
http://www.amazon.com/Daily-Guitar-Reading-Technique-Studies/dp/0786682809

Make sure you get the large-print edition, because the "normal" edition is actually a pocket-sized "Quick Guide" that is tiny.

This has 30 daily studies that will have you sight reading full chords in 1 month if you work on it every day.

Another great resource for sight reading is this one from Berklee:
http://www.amazon.com/Reading-Studies-Guitar-Positions-Multi-Position/dp/0634013351

I also recommend a theory book, for example Berklee's Music Theory 101 books 1 & 2 as used at Berklee College of Music:
http://www.amazon.com/Berklee-Music-Theory-Book-Edition/dp/0876391102

Get these, a Real Book for jazz standards, and some note-for-note transcriptions of albums you want to learn for the metal stuff. Books are available for lots of major label albums if you search for them. Make sure you use a metronome to practice. You don't need anything fancy; something like this will work just fine:

http://www.amazon.com/Qwiktime-QT3-Qwik-Time-Metronome/dp/B0002F75EM/ref=zg_bs_11965901_9

Hope this helps! Have fun.