There are many variations on line sheets but there are similar types of information on many of them.
Your Brand or Logo
Your brand or logo should be front and center. This helps remind them who they are working with as well as build brand recognition towards your website in the future.
You should include your contact information in a prominent location so the companies can easily find out how to contact you. The minimum information should be your email address and physical address. Often times a phone number and fax number will also be included. You can search for line sheet example via http://www.brandboom.com/ and get the information about the line sheet.
Make sure you provide enough information about your book so they can make a buying decision. At a minimum you should include the cover, title, list price, and a wholesale price. We also recommend including a description and potentially a link to a sales page for the book, either on your website or on Amazon.
While you often have to work with the billing system a company prefers, it doesn't hurt to have your preferred billing method on your line sheet. Some billing information includes the forms of payment accepted (credit card, check, bank transfer), the payment terms (net 30, net 60, consignment, etc), any bulk discounts offered (10% off for purchases of more than X books), any minimum order amounts, and whether or not shipping is included in the price.