I dont see the signup link or so..

who to register with them and what is the average fee?

You can't register with them (well, you can but you don't want to.) You need to go through a reseller and as a result your fees will vary. Go to their reseller directory (http://www.authorize.net/solutions/merchantsolutions/resellerdirectory/) and contact a few of their listings. Ask for price quotes for a merchant account and Authorize.Net. The quotes you get will vary widely so make sure you do shop around so you can get the best deal.

got it, btw i saw many links in the reselle directory, anyone know the average setup,monthly fee?

around couples of dollar or much more?

Average setup is about $100. It can be less then that, though.

Average monthly fee is about $15.

authorise.net is only for USA merchants?

Yes, Authorize.Net only works with U.S. merchants currently.

Almost every Internet merchant processor is a reseller of Authorize.Net and should be able to help get you both a merchant account and Authorize.Net gateway account as an "all in one" bundled solution.

In terms of average pricing - I have seen a LOT of $0 Setups for Authorize.Net in the market now and I would almost go so far as to say that it is really the norm now for most competitive/aggressively priced Internet merchant processors.

The monthly cost is usually around $10-15/month. I have seen some higher, not many lower than that. The other value-added fees can vary quite a bit such as if you want the Authorize.Net recurring, anti-fraud services and so forth.

The per transaction side is usually $.05-.10 with few exceptions.

Authorize.Net is the most well known gateway but there are naturally a lot of other options out there including those with either better technology, more built-in value added features, better pricing - or all of the above.

Hope the above info is helpful for you and best of luck with your search!