I've been playing around with the setup for awhile and I'd like to share my experience with you guys
My CD/Cassette player doesn't have standard RCA outputs, instead it uses a clamp type 6 ohms output, so I bought a 3.5mm Stereo Jack to 3.5mm Stereo Jack (about $3 at Fry's, Radio Sack has it too). I plug one end into the headphone jack of the stereo player (I had to use an apdater because it has a big hole), the other end I plug into the LINE-IN of the sound card. My motherboard has AC'97 sound built-in. After many recording trials, I found the sound quality was crappy. So I disabled it, and used a SoundBlaster Live card.
The hardware setup is relatively easy and straight forward. The hardest part is the recording applications. There're many of them out there. Some are excellent but they can only record in WAV format then you have to convert it to MP3 later by using the same software or a difference one which I found too much hassles. Recording in WAVE format requires a huge hard disk space (approx. 10MB/min, typical audio tape is 90 min = 900 MB) Besides, I don't bother to use all their bells and whistles. I just simply want to convert some old tapes in to MP3 quickly.
After doing some researches, I found
Super MP3 Recording and
Advanced MP3/WMA Recorder are perfect for MP3 recording. They record in MP3 format
on the fly i.e. they don't take much disk space and the output is in .MP3.
Super MP3 Recording can record with NOISE REDUCTION, but no VBR (variable bit rate) available.
Advanced MP3/WMA Recorder has VBR option with no no reduction.
After playing around with both of them, I decided to use Super MP3 Recording. The best one, IMO.
Send me an PM for any further question. Good luck!
EDIT:
one hour MP3 needs about 60MB @ 128kbps, 44.1 khz or 1MB/min
By the way, I'm trying to convert VHS tape in to digital format. I still can't decide which is the best output format (.mpg, .avi or SVCD) Your help and opinion are greatly appreciated.