[quote name='IXI Dragunz IXI']Where do I call to cancel? I didn't get an e-mail yet.[/quote]
I don't want to sound mean or anything, but from what you have been posting in here, it looks like you are getting in over your head.
How many offers are you signing up for at once? And why aren't you keeping a record of what/when/how much $/cancellation information? When you sign up for an offer, click to its "Terms of Service" section and copy down an address and phone number (or email addy).
Don't let a bunch of silly trials potentially hurt your credit score.
EDIT: And this is more a warning to everyone:
DON'T rely on the trial companies to send you emails with account information! In all the trials I have done, I would bet that a little under 50% of them DO NOT get an email out promptly to me (if at all). That is why you need to collect and keep track of the information yourselves.