Below are the links that I will use in today's presentation.
In Section 1.3.3 of the text, there is a link at thge bottom of the page to Historical Background: Function and Related Concepts. There Leonhard Euler is mentioned along with others in a discussion of the development of the notion of function.
The footnote-type link on Euler's name takes you to a popup note window with a link to the MacTutor page for Euler.
Another source is Wikipedia.
Yesterday, the Math in the News article in Math Gateway was about a paper that John Derbyshire had written for The Wilson Quarterly. Today there is a new article, but yesterday's is stored in the Archive. Derbyshire is an excellent author. He wrote Prime Obsession: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics, which won the first MAA Euler Book Prize this year.
The online magazine Convergence, part of the Mathematical Science Digital Library (MathDL) is dedicated to the use of the history of mathematics in the teaching of mathematics. Here you can find a gallery of portraits of mathematicians, information on events surrounding the Euler Tercentenary Year, and 38 articles, reviews, and other materials involving Euler in some way.
If you are an MAA member (or subscribe), another resource in MathDL is Classroom Capsules and Notes. These are pdf files (from JSTOR) of classroom notes from the three MAA print journals. Searching over "euler" turns up eight articles related to Euler in some way or other.
Also, in MathDL, you can find in the Journal of Online Mathematics and its Applications (JOMA), an article Global Positioning System and Imagery Collection that describes the West Point project on the use of GPS systems and Google Earth.