I need an Excel Template for my Business Estimates and Invoices

I need an Excel Template or something I could use over and over again. A template for my Invoices and Estimates I will write up for my customers. When I go to write up an estimate or invoice for my customers I need a template with all my business information already inserted and all I have to do is insert the date, job information and cost or total for the job. I dont know if this is possible but maybe from my iphone too.