Help Desk - Payment and Pricing

Is it safe to give out my credit card details online?
Why does the same book have a different price?
What is your Pre-order Price Guarantee?
I used to have my credit card details saved on your website, but now I can't find them. Where are they?
Do you match the price of a competitor's product?
Can I have a discount if I order in bulk?
Can you send me a tax invoice?
I have a voucher code, how do I use it?
Can I email Fishpond My Credit Card details?
How does your site calculate sales tax?
Can I use A debit Card?
When will my credit card be charged?
What payment methods can I use?
Do you offer student discounts?