How do i hook up my tascam 414 portastudio to my PC??

Assuming you want to keep your recordings at the highest possible quality, wouldn't it also work if you had an outboard component CD recorder? That way you retain the highest resolution at the first analog-digital step and once it's on CD you can rip to your heart's content or run it through the mixer again.

I have a Pioneer Elite PDR-509 that I have used for years. There are several 'professional' decks made by Tascam, Marantz, HHB and others that add the ability to use vanilla CDR's and CDR/W's instead of CDR-Audio and CDR-A-R/W media as mine uses and some can defeat the SCMS codes so you can do digital-digital multiple generation copies. Home audio CD Recorders will only digitally copy a first-generation digital original, unless the source was was made on a PC. Then it's always considered first-generation. The cost of the media isn't that much different these days. A standalone CD Recorder would also let you digitize those LP's and tapes you have hanging around or record Live through your mixer to CD. How about that!!!

There are plenty of them on eBay cheap and I'm still looking for the right one in case mine should ever decide to die. I see 7 pro models right now on eBay. I'd look for one that has Coaxial Digital inputs and outputs as well as Optical ones.

As for hooking up your Tascam, that would depend a lot on what sound processing software and soundcard you have - not my strong suit as I still do everything in the analog domain prior to cutting the CD and then ripping it to MP3 for portability and fast access. The physical hookup would be Line Out to Line In. After that it's all software.