How to start a calling card business using voip

I´m about to start a calling card business and I need to read more. Are there any good books covering this, or something comprehensive on the net. Most info I find is company-related and I wish to find something covering the different alternatives regardless of company.

Welcome to VoIP User T_Kerje.

No such thing really as a calling-card business book. Have you read through the existing threads on here? We've had quite a few on this subject:-

http://www.voipuser.org/search/results. ... &hl=en

Thanx for your reply. I read everything and I understand there are many obstacles and many technicalities I have to learn. I will probably ask many more detailed questions as I go on. I see one problem many optimistic starters have is they don´t realize the competition and marketing problems. My idea is to start slowly to learn and use it in Sweden (where I live) and probably not makinga lot of money here since there are already 44 different voip card providers here. But my BUSINESS idea is to implement the techniques in Morocco which is my second country (plan to move there). In Morocco there are CERO cards and international calls start from 0.60 Euro from phone boots. I successfully started two other business and I´m convinced this will work also.
I guess I will start with the cheap options to learn. I have a few small questions here. 1. Does A2billing combine with Trixboxpro? 2. A really beginners question: Do I need a hardware gateway to my server or could it be a software or some other solution? If so, what gateway would I buy for lets say at least 10 simultaneous calls? 3. Do I need to install an OpenSER or OpenSIP as well? 4. I bought a Digitum TDM411B card with 4 analog ports. Will this work with the software?