Christ... I answer these emails all day long... come home to relax and what do I find? This!
Ok..
If you want to know what you're going to be paying, there's a handy dandy fee table right here.
http://pages.ebay.com/help/sell/fees.html
Basically the first table (Insertion Fees) are based on either the starting price you set or the hidden reserve price you set. There is also a Final Value Fee which is based on the amount it sells at. The %'s are to the right of the insertion fees.
You will also be charged for any listing upgrades you choose like extra pictures, themes, "Featured" listings and so on. Rates for these, can be found on that page also, by clicking the "Show" button next to each feature.
There are even selling tools you can subscribe to, to help you list.
Just a friendly warning, READ EVERYTHING. Everything you do on there is binding, since you're not actually Buying anything from eBay, you're buying from other members. Think of it like a global buy and sell. eBay is just a venue, and they'll help you out where they can.
But if you buy things outside of an auction, or send western union money orders to nigeria in an anonymous name for items that sound too good to be true (guess what...) then you can kiss your money goodbye because there is no way to trace that kind of thing.
Stick to the rules and guidelines and you'll be ok.