A: Access to explosives.
The good news is that explosives can be hard to come by, but that doesn't keep the brothers from dreaming of the day when they can lay hands on some.
There's a detailed discussion of Semtex going on at al-Shmukh forum, about how to make it at home, etc.
Step one: grind RDX crystals into a fine powder with a rolling pin. Note that this can be stressful work, so be sure to take your time and take frequent smoke breaks...
2. Hand grenades (holy and otherwise)
Meanwhile, over at the eMujahideen forum they're drooling over images of hand grenades and Arabic translations of old military manuals.
Tip: after pulling the pin, release the lever, and count to five, for the Five Pillars of Islam, before throwing the grenade. Allahu Akbar!
© 2003-2011 society for internet research