3 steps after the Amidah: Yoma 53b
Where one's eyes should face, if praying in Israel: Yevamot 105b
Where one's heart should "face", when praying in Israel: Yevamot 105
Standing with legs facing the same way: Berachot 10b
Legs together: Rashi Berachot 10b "VeRagleihem"
Order of Bowing: Berachot 12a
Method of Bowing: Berachot 12b, Tos. Berachot 12b #1
Spinal damage for not bowing for "Modim" for 7 years: Bava Kama 16a
For a Laborer Standing in different types of Trees: Berachot 16a
For a Self-Employed Laborer Standing in different types of Trees: Berachot 16a
Holding Phylacteries or a Torah Scroll during the Amidah: Berachot 23b; Succah 41b
Holding a Citron while reciting the Amidah on the holiday of Succot: Succah 41b
Holding anything while praying the Amidah: Berachot 23b; Succah 41b
Yawning, spitting, belching and sneezing during the Amidah: Berachot 24a-b Passing gas during the Amidah: Berachot 24b
Removing lice from one's clothing during the Amidah: Berachot 24a-b
Reciting it while one is unclothed, by keeping his head beyond a divider between his head and his unclothed areas: Berachot 24b-25a
Reciting a blessing and donning a tallit during the Amidah: Berachot 24b
Praying in a loud voice shows one is of little faith, failing to recognize that Gd hears all: Berachot 24b
Prayer is termed "lechishah" - whispering: Taanit 8a
Praying loudly to improve one's concentration: Berachot 24b
Raising one's voice in prayer imitates the ways of false prophets: Berachot 24b