i am a complete beginner in all of this.

i have an old cd player but i think it's good enough, i want to know about transports and all that stuff,

i guess, is there a newbie guide?

I don't know about the newbie guide, but we can answer your questions some.
A transport is exactly that it transports the disc. All cd players consist of a transport where the CD spins and is read by a laser and a DAC (Digital-Analog Converter) translates the stream of 1s and 0s into an analog electrical signal. In order to reduce the interference that one part has on the other, some manufacturers separate these two parts into separate components. In real terms, if you get a transport, you will need to get a separate Digital-Analog Converter to translate the digital signal that is put out by the transport into an analog sound that an amplifier can amplify and the speakers can convert into sound. A good example of this your computer. Your CD-ROM is a transport, it reads the digital data which is then transmitted to your sound card. The sound card now converts the digital stream of 1s and 0s into an analog signal. The amplifier section of the soundcard augments the signal and this is transmitted to your PC speakers.

can i use an old cd player as a transport and run it to a di/o?

Only if the old cd player has a digital output, which means unprocessed digital data is being passed through them. A connection out from the RCA jack or something similar would've already been "processed" by the DAC built into the CD player.

The player needs to have a digital output - look on the back and see if there is one labeled.

ok it does, then what?

sorry, this whole concept is completely foreign to me!

and thanks for all the help!

If the transport has a digital out, you can run it through a digital-to-analogue convertor (DAC). Many new A/V receivers have DACs built in.

Transports can be distinguished by their ability to handle error correction (thus getting the maximal number of correct bits off of a CD) and by the accuracy of their clock -- so that they output digital bits with even precision. If the bits come out at a wrong clock rate, a type of distortion known as "jitter" occurs.