The following table lists some standard parts that get used a lot:

5V 2A Switching Wall Wart Emerson Network Power DA-12-050US-M Mouser 826-DA-12-050US-M 2.5mm PCB Mount Barrel Connector  SwitchCraft RAPC712BK Newark 03M4244 2.0mm PCB Mount Barrel Connector  SwitchCraft RAPC722BK Newark 03M4245 Ferrite Bead FAIR-RITE 2743001111 Newark 97B0025 .1 uF Ceramic Capacitor 2.54mm PCB Kemet C320C104M5U5TA Newark 32K5474 TO-220 Heat Sink, Clip-on Multicomp MC33282 Newark 09R3167 TO-220 Insulator Multicomp MK3306 Newark 50P9593 TO-220 Fastener Kit Multicomp MK3311 Newark 50P9672 TO-220 Heat Sink Fischer SK 409/25,4 STS Newark 34M8466 RJ25 Jack 6PC6 PCB Mount AMP 5569026-1 Newark 42K7313 10/100 MagJack PCB Mount Stewart/BEL SI-50170-F Digikey 380-1103-ND 28 PDIP Socket AMP 1-390261-9 Newark 52K3282 10 uF Electrolytic Capacitor 25V 2.54mm PCB Panasonic ECA1EAK100X Newark 38K1156 16 MHZ Crystal PCB Mount Citizen HC49US16.000MABJ-UB Newark 59K8183 16 MHZ Ceramic Resonator PCB Mount Abracon AWCR-16.00MD Newark 13J1998 25 MHZ Crystal PCB Mount Citizen HC49US25.000MABJ-UB Newark 59K8191