Avid MBOX 2 by Lerm7
This is an older series audio interface/digital converter/preamp for Pro Tools LE made by Digidesign. They run for about $350 (USD) now-a-days, and it is important to note that they only function with Pro Tools software. This was my first interface, and it helped me to understand the concepts of basic recording.
This baby records at up to 48khz with 24-bit resolution. Backside includes 2 inputs for mic (XLR)/DI (1/4")/line (1/4"), left and right monitors outputs, in and out s/pdif, midi in and out, and a bus powered USB. Each of the 2 main inputs has a built-in preamp. The front panel has a headphone jack and volume knob, monitor volume knob, mix knob, mono button, phantom power button, and both inputs have a volume knob, pad button, and DI/Mic button. The item comes with Pro Tools software.
If you're starting out in the world of recording and are looking for a cheap interface, this is a great option. It allowed me to learn how to use Pro Tools. The great thing about Pro Tools is that once you learn the LE version, it becomes a lot easier to use the HD version because the majority of the features and controls remain the same.