To do Let's Plays?
-
Microphone ($10 - $200 just depends on what you get)
This is essential to doing LPs. You need some method of recording your voice, and a microphone is typically where that method resides. Alternatives to standalone mics are built-in mics (like in a laptop), or even an iPod Nano 5G (I personally went this route before).
-
Capture Cards ($10 - $500 jsut depends on what you get, and for what console)
This is another essential to LPs. In order to show video feed, you need to get a device to capture said feed. I haven't any experience with these, but frequently recommended devices* are:
Dazzle
Hauppauge HD PVR
EzCAP (not EasyCAP)
*This is only for home consoles, examples being N64, PS1, PS2, PS3, GameCube, Wii, Wii U, Xbox, Xbox 360
And if you're looking to 3DS capture, you can only do it this way:
3DS Capture Board
-
Editing Software (usu. $250+)
This isn't so much essential as it is recommended. In order to splice your audio feed with video feed, you'll need something to get that accomplished. SOme people use Windows Movie Maker which is free, but I personally recommend
Sony Vegas.