question for travel agents please

Is there help anyplace to learn about how to start my own online travel 
agent? I found established online travel agent web sites for sale on 
ebay. They range anywhere from $1.00 up to $5,000.00  
I dont know why they have such a big price difference. These are real 
travel agency's and not the ones that just give you %50 percent 
commission. Does anybody help for a newbie in the online travel agent 
field? I have been trying to find prices on subscribing to worldspan or 
Sabre and I cant find any price info on that either. I emailed worldpan 
and sabre and they never emailed me back. I found an old article from 
1999 on google that said the price is 40.00 a month. But that was in 
1999. What is it now? I dont want a host agency to book through, I want 
to open my own. Also, whats better? Worldspan or Sabre? Thank you for 
your time