My Mom wants to go to canada, but doesn't have the money. I am planning on buying her plane tickets, but I'm not sure if these online ticket purchases can be trusted. I searched expedia.com and found tickets to be at about ~250, with american airlines. I went to the american airlines webpage and found one to be about ~600 and the rest to be about ~250. Any reason why such a big price difference? I just did a basic search. Has anyone had experience with buying airline tickets online?