if the problem is, that you need to get a file from the pc to your miggy (and you´re not able to get miami work, yet) the easiest solution should be a nullmodem cable. in combination with a normal terminal program on both sides you can transfer the needed files.
else, use your tcp connection for ftp, samba, nfs (or whatever)
ftp/nfs servers for the pc come with xwin, nfs for amiga is availibe on the aminet (nfsd by j.walton) ftp clients should be no problem.
if you just need to copy files in one direction (pc -> miggy) better use smbmount (also on aminet)