How can I know that an Affilaite Marketing Program open for foreign membership? What should I know as an international affiliate with reagrads to payment of commissions(i.e tax and foreign account considerations)?

Most affiliate programs are open to foreign membership, though some accept only US and some restrict Asian countries. It depends on the agreement for each program and what types of products they sell. Kolimbo.com has a lot of programs that allow foreign membership, please try there and contact one of the support people listed and they can help you.

That will vary by site. You need to look into the particulars for each site. The only tax you have to worry about is that due in your country for income.