E-bay is the best way to sell tix. Stubhub is ok too.
Paypal is the best payment method for them to use.
As far as fees, if you sell something on e-bay, the auction will cost you around $4, then they will charge you a "final value fee" which will be a few more dollars. Then, once you get the person's payment in Paypal, they take about 3% off the top. Keep all this in mind when you figure out how much to charge. Also look at the other e-bay auctions for tickets and see which ones are selling and at which prices. A lot of times the "ticket broker" auctions go unsold because they charge WAY too much!