Posted By: 
warshawlawand I usually offer trades in my buy-sell post--but no one has the damned cards I want (jus' keedin').  
Seriously, I bring a big stack of trade bait to most every show I attend. 
My online tading experience has been good, and I second the things that the others have been saying about safety: know your partner.  It's kinda like Sam Kinison's great take on sex and VD: if you don't trust the ****y, don't f*** the ****y.  Same idea for trading: I only trade through the mail with people I know and trust.  If Joe Blow Lurker offers me a trade, I am unlikely to do it unless he sends the cards first.  Someone well known and well respected, and I go ahead.